AFNS Most Repeated Chemistry MCQs
Question | Answer |
Which of the following sulphur compounds shows +4 oxidation state? | H₂SO₃ |
Low CO₂ favors stomata to? | Open |
Ripening of fruits is hastened by which gas? | Ethylene |
The natural rubber is a polymer of? | Isoprene |
Seventh period consists of normal elements? | No |
Halogens exist in which states? | All |
Two ice cubes are pressed over each other and unite to form one cube. Which force is responsible for holding them together? | H-Bonding |
The reaction of sodium acetate with soda lime gives? | Methane |
Picric acid is formed when which compound reacts with nitric acid? | Phenol |
X-rays are produced when a stream of electrons in an X-ray tube? | Strikes the metal target |
The reaction in which energy is evolved is called? | Exothermic |
Which is a buffer solution? | Blood |
Lead contains? | Sulphuric acid |
How many molecules are there in one mole of H₂O? | 6.02 × 10²³ |
Numerical value of Avogadro’s number? | 6.02 × 10²³ |
Heating of food in a microwave oven is an example of? | Solvent extraction |
Main component of an organic compound? | Carbon |
The main source of organic compounds? | Petroleum (if missing: Coal, if both missing: Coal tar) |
The reactant which is consumed earlier is called? | Limiting Reactant |
Neutron is discovered by? | Chadwick |
Which one is not a base? | BF₃ |
Lattice energy is also called? | Lattice enthalpy |
If Nitrous oxide gas is inhaled, it causes? | Laughter/Laughing |
Ionic bond is formed by? | Positive and Negative ions |
Color of chlorine gas? | Yellow-Green |
Which series includes the Hydrogen Atom? | Balmer Series |
Which scientist played an important role in the periodic table? | Mendeleev |
760 torr is equal to how many atm/Pascal? | 1 atm / 101325 Pascal |
Nature of bonds in diamond? | Covalent |
How many types of intermolecular forces are there? | 3 |
When compressed Acetylene/Hydrogen is allowed to expand, it causes? | Frostbite |
Question | Answer |
What is the boiling point of water at Mount Everest? | 70°C |
Ethyl acetate is the ester of ethanol and? | Acetic acid |
Which one halogen is a? | Bromine |
What is the percentage of sodium in NaOH? | 57.48% sodium, 40% oxygen, 2.52% hydrogen |
Molarity of HCl is? | 12.1 M (Molar) |
Molarity of ammonium hydroxide (NH₄OH) is? | 14.5 M |
Glucose reacts with bromine water to produce? | Gluconic acid |
Total number of d-block elements in the periodic table? | 40 |
Ionic bond is formed by? | Positive and Negative ions |
Reacting bromine with benzene in the presence of sunlight results in? | Addition Reaction |
Ammonium Chloride is in nature. | Acidic |
Alcohol reacts with carboxylic acid in the presence of? | H₂SO₄ |
Acyl Chloride is formed when carboxylic acid reacts with? | Thionyl Chloride (SOCl₂) |
In an exothermic reaction, heat is? | Released |
Which gas diffuses more rapidly, H₂ or N₂? | H₂ |
Heterogeneous mixtures can be separated by? | Distillation/Filtration |
Alkali is a ? | Base |
Effusion and Diffusion Process are completely understood by? | Graham’s Law |
Spontaneous reaction is? | Exothermic |
Down’s cell is used to prepare? | Sodium Metal |
A law in which temperature is kept constant is called? | Boyle’s Law |
Water is sparingly soluble in? | Ethane |
Dalton’s Law is about? | Atmospheric Pressure |
Percentage of carbon dioxide carried in the form of bicarbonate in plasma is? | 70% |
One or two species having the same atomic number and the same position in the periodic table are called? | Isotopes |
The Laughing Gas is? | N₂O |
In the periodic table, elements having different properties are? | Lithium and Barium |
Elements that have more than one form are called? | Allotropes |
Empirical Formula of Water is? | H₂O |
In gases, when temperature increases, viscosity of gases? | Increases |
Which scientist played an important role in the periodic table? | Dimitri Mendeleev |
Elements at the same position in the Periodic Table are? | Isotopes |
Covalent Bond is not found in? | Iron |
Elements that have the same atomic number but different atomic masses are called? | Isotopes |
Which of the following are diagonal to each other? | Lithium and Barium |
Question | Answer |
Which one is not a base? | Hydrochloric acid |
Lead contain; | Hydrochloric acid |
In which law, the pressure is kept constant? | Charles’s Law |
Color of chlorine is; | Yellow-green |
Who discovered neutron and when? | Chadwick in 1932 |
Numerical value of Avogadro’s number; | 6.02 x 10²³ |
How many molecules are there in one mole of H₂O? | 6.02 x 10²³ |
760 torr are equal to how many pascal? | 101325 |
The reactant which is consumed earlier and gives least quantity of product is called; | Limiting reactant |
When compressed hydrogen is allowed to expand rapidly, it causes; | Respiratory disease |
Which scientist played a role in the periodic table? | Dimitri Mendeleev |
How many types of intermolecular forces are there? | 3 |
The nature of the bond in diamond is; | Covalent |
Lattice energy is also called as; | Lattice enthalpy |
Inhaling Nitrogen oxide causes; | Laughter |
The main source of organic compound is; | Coal |
A law in which pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature is called; | Boyle’s Law |
Water is sparingly soluble in; | Ethane |
Down’s cell is used to prepare; | Sodium metal |
Effusion and diffusion processes were completely understood by; | Graham’s Law |
Alkali is a; | Base |
Which of the following gases diffuse rapidly? | Oxygen |
Which product is formed when Acyl chloride combines with carboxylic acid? | Acetic anhydride |
What will be the effect on the rate of reaction when the temperature increases? | Rate of reaction increases |
What will be the energy on the product side, when an exothermic reaction occurs? | Energy decreases |
Mass of sulfur in 24.5g of H₂SO₄; | 8g of sulfur |
1 Calorie = ? | 4184 Joule |
Which has the maximum “n” shell electrons? | n=16 |
The stability of an atom is directly proportional to; | Isotopes |
What is ethyl acetate? | An organic compound (C₄H₈O₂) used in nail polish remover |
When Carboxylic acid and Alcohol combine and form an ester, which catalyst is used? | Sulfuric acid (H₂SO₄) |
Which one of the halogens is liquid? | Bromine |
Total number of d-block elements in the periodic table; | 30 |
There are——— Groups in the periodic table; | 18 |
Two or more forms of an element that contain equal numbers of protons but different numbers of neutrons in their nucleus are called; | Isotopes |
What is the name of the process in which oxygen is removed? | Reduction |
Which one is alkaline among the following? | Ammonia |
Which acid is used in the body to help digestion? | Boric acid |
CNG stands for; | Compressed Natural Gas |
Picric acid is formed when———– reacts with nitric acid. | Phenol |
Down’s cell is used to prepare; | Sodium metal |
Dalton’s Law is about; | Partial Pressure |
A heterogeneous mixture can be separated by? | Distillation / Filtration |
What law is when pressure is inversely proportional to volume? | Boyle’s Law |
What law is when the pressure is constant? | Charles’s Law |
Melting point of NaCl is? | 801°C |
Calcium Carbide on reaction with water gives; | Acetylene gas and calcium hydroxide |
The shape of an orbital is determined by which quantum number? | Azimuthal Quantum Number |
Size and energy of an orbital are determined by? | Principal Quantum Number |
What is the boiling point of water at Murree? | 98°C |
Question | Answer |
The covalent radius of Cl atom is: | 99 pm |
CsF is an ionic compound because: | Low IP of Cs and high EA of F |
Molecular orbitals are filled with the available electrons according to: | Hund’s rule |
An ionic compound will dissolve in water only if: | Hydration energy is high and lattice energy is low |
A chemical bond between two atoms having the difference of electronegativity 1.7 then which statement is correct: | Bond is 50% ionic and 50% covalent |
Which of the following compound has ionic bond in it: | NaF |
Which of the following is most electronegative element: | F |
The energy that is required to remove an electron from an atom is called: | Ionization potential |
The tendency of bonded atom in a molecule to attract shared pair of electrons is called: | Electronegativity |
Which of the following element has highest ionization potential: | Rb |
In a group of periodic table, ionization energy: | Decreases |
The strongest bond is: | C≡C |
Which of the following is not correct: | Single bond is shorter than double bond |
In which of the following pairs, do the elements form a compound by sharing electrons: | Carbon and chlorine |
Molecular orbital theory explains well: | All of above |
The expected geometrical shape of molecules which have sp³ hybridization is: | Pyramidal |
Which of the following compounds have ionic, covalent and coordinate bond in it: | HNO3 |
Which of the following species has highest bond order: | O₂⁺ |
The study of heat changes accompanying a chemical reaction is known as: | Thermochemistry |
If an endothermic reaction is allowed to take place very rapidly in air, the temperature of the surrounding air: | Decreases |
In endothermic reactions, the heat contents of the: | Products more than that of reactants |
The majority of reactions which give stable products are: | Exothermic |
It is noticed that energy in the form of heat is either evolved or absorbed as a result of a: | Chemical change |
In a chemical change, the energy in the form of heat will either be evolved or absorbed and this is called: | Heat of reaction |
The energy units in which heat changes usually expressed in SI-system are: | Joule |
The subject matter of first law of thermochemistry is based on: | First law of Thermodynamics |
A process which takes place on its own from a non- equilibrium state towards an equilibrium state is termed as: | Both Spontaneous and Natural process |
Which one of the following is not related to spontaneous process: | Artificial |
Neutralization of a strong acid with a strong base is: | Both Natural acid base reaction and Spontaneous acid base reaction |
When a piece of zinc is added to the copper sulphate solution, colour of solution disappear: | Blue |
The reaction of Zinc with copper sulphate solution is an example of: | Spontaneous redox reaction |
A reaction will also be called a spontaneous if: | It does not need energy to start with |
Burning of coal and hydrocarbon in air are examples of: | Both Spontaneous reaction and Natural reaction |
Some non-spontaneous processes can be made to take place by supplying energy to the system from: | All of above |
By state, we mean the: | Condition of a system |
When no work is done by the system: | The volume of system decreases |
Question | Answer |
The experimental evidences for the existence of atomic nucleus comes from: | Scattering of alpha particles by thin metal foil |
When alpha particles are bombarded over Be atoms, neutrons are released along with: | Carbon |
The Rutherford experiment of using a stream of alpha particles on a piece of gold foil proved that: | Atom had a great empty space in it |
Which of the following observations was seen by Rutherford when alpha particles were bombarded over gold | Majority of alpha particles passed through foil without deflection |
foil? | |
The mass of alpha particle is equal to: | Four times the mass of one proton |
Rutherford’s model of atoms failed because: | It did not account for stability of the atom |
Max Planck proposed quantum theory in: | 1900 |
Quantum theory explained: | Both emission and absorption of radiations |
According to Planck energy travels in a discontinuous manner and it is composed of large number of tiny discrete units called: | Quanta |
The value of Planck’s constant ‘h’ is: | 6.625 x 10^-34 Joule second |
According to Planck, in case of light, the quantum of energy is often called: | Photon |
Wavelength is the distance between two adjacent crests or troughs and expressed in: | nm |
Greater the wavelength associated with the photon: | Smaller is its energy |
Energy of a photon is related to: | All of above |
Greater the wave number of photons: | Greater is the energy associated with them |
Splitting of spectral lines when atoms are subjected to a strong electric field is called: | Stark’s effect |
The velocity of photon is: | Independent of its wavelength |
Bohr’s model of atom explains spectrum of: | H atom only |
Transition from various energy levels to the lowest energy level gives: | Lyman series |
P-fund, Bracket and Paschen series lie in: | Infrared region |
Balmer series lie in: | Visible region |
The force which holds together two or more atoms or ions to form a large variety of compounds is called: | A chemical bond |
The theory of chemical bonding has been a major problem of: | Modern Chemistry |
Chemical reactivity of elements depends upon their characteristic: | Electronic configurations |
Which of the following elements is not stable: | Kr |
Elements combine together due to inherent tendency to stabilize themselves by: | Losing electron, Sharing electrons, Gaining electrons |
Which of the following is a noble gas: | Ne |
The tendency of atoms to attain a maximum of eight electrons in the valence shell is known as: | Octet rule |
In the chemical combination of sodium and hydrogen to form NaH: | Hydrogen atom gains an electron |
In the chemical combination of hydrogen and fluorine to form HF: | Both atoms share the electrons equally |
Which of the following molecules is not formed according to octet rule: | XeO3 |
According to modern theory of chemical bonding, atoms form bonds as it leads to a: | Decrease in energy |
When two hydrogen atoms approach each other: | Forces of attraction and repulsion operate simultaneously |
The bond length between atoms of hydrogen in the hydrogen molecules is: | 0.0754 nm |
Which of the following has smaller size: | Fe³⁺ |
In a group of periodic table, atomic radii: | Increases |
In a period of periodic table, atomic radii: | Decreases |
Which statement is true for Na and Na⁺: | Size of Na is greater than Na⁺ |
As the nuclear charge increases, the pull on the electrons is increased and size of an atom: | Decreases |
The radius of the ion while considering it to be spherical in shape is called: | Ionic radii |
The decrease in radius is larger for: | Trivalent ions |
The increase in size of the anion is due to: | Increase in electron-electron repulsion |
Question | Answer |
8. Rate of evaporation and rate of condensation at equilibrium: | Become equal |
19. At sea level and at 100°C the vapour pressure of | 760 mm Hg |
water in an open system is: | |
20. A liquid on evaporation causes: | Cooling effect |
21. Escape of high energy molecules from the surface of a liquid is called: | Evaporation |
22. Which of the following liquids has low vapour pressure at 25°C: | Water |
23. The boiling point of NH3 is maximum among the hydrides of group V elements due to: | Enhanced electronegative character of Nitrogen |
24. Heat of vapourization for liquids with strong dipole- dipole forces will have: | Very high values |
25. Trend of boiling point of halogens from fluorine to iodine is that it: | Increases |
26. Liquids have low boiling point provided: | High vapour pressure at given temperature |
27. Molar heat of vapourization of water is: | 40.6 KJ/mole |
28. Boiling point for water under 23.7 torr external pressure is: | 25°C |
29. Boiling point of a liquid at high altitudes: | Lower at high altitude |
30. Cooking time reduces in a pressure cooker because: | Boiling point of water increases |
32. Boiling Point of a liquid is high when: | Hydrogen bonding is present |
33. Boiling point of a liquid depends upon: | External pressure |
34. In the industrial purification of glycerine, its boiling point is reduced from 290°C to 120°C by: | Decreasing external pressure |
35. Many organic compounds and biological tissues behave as: | Liquid crystals |
36. Which is not the use of liquid crystals? | Energy supply in electrical devices |
37. Oscillographic and TV displays also use: | Liquid crystal screens |
38. Amorphous solids are characterized by: | Possessing irregular arrangement of atoms |
39. Which one of the following is pseudosolid? | Glass |
40. Hydrocarbons which generally have high molecular masses, exist in: | Solid form |
1. Neutron was discovered by: | Chadwick |
2. The e/m value for positive rays is maximum for: | Hydrogen |
3. The nature of positive rays depend on: | All of the above |
4. Which of the following was discovered first? | Charge of electron |
5. Which of the following particles has longest wavelength, if they have same speed? | Electron |
6. Maximum potential energy that an electron can have within the atom is: | Infinite |
7. Charge to mass ratio of electron was discovered by: | J.J. Thomson |
8. When an electric current is passed through discharge tube at low pressure, cathode rays are emitted from cathode these rays consist of: | Negative particles |
10. Charge of an electron is: | 1.6 x 10^-19 C |
11. Mass of simple electron is: | 9.1 x 10^-31 kg |
12. The charge over mass ratio of electron is: | 1.7588 x 10^11 C/Kg |
13. Charge on electron was discovered by: | Millikan |
14. Proton was discovered by: | Goldstein |
15. Which one of the following particles has a mass 1/1836 time, that of hydrogen? | Electron |
16. Negatively charged particle nature of cathode rays was first demonstrated in 1895 by: | Hittorf |
17. With the reference of e/m ratio of anode rays, the e/m ratio of cathode rays is: | Greater |
18. Which one of the following statements is true about discovery of neutrons? | These particles were formed by the bombardment of α-particles on Beryllium |
19. Anode is the surface on which probability of finding electron is: | Less than 10% |
Question | Answer |
23. The product of pressure and volume remains constant when temperature and quantity of gas is: | Kept constant |
24. The ratio of volume to temperature on Kelvin scale is constant according to: | Charles’s law |
25. The graph between pressure and volume at constant temperature for a gas is: | Isotherm |
26. The density of a gas is directly proportional to pressure, inversely proportional to temperature, and directly proportional to: | Momentum |
27. If absolute temperature of a gas is doubled and the pressure is reduced to one half, the volume of the gas will be: | Increased four times |
28. Absolute temperature of a gas is proportional to: | Translational Kinetic energy |
29. The highest temperature at which a substance can exist as a liquid is called its: | Critical temperature |
30. Keeping the temperature constant, if the gas is expanded: | Pressure will decrease |
31. At constant temperature, when pressure of a gas is plotted against volume, the curve is: | Parabolic |
32. A gas is heated in such a way that its volume and absolute temperature both are doubled. The pressure of the gas: | Becomes half |
33. If the number of gas molecules is doubled in a certain volume, the pressure is: | Increased to half |
34. At the same temperature, which substance has high kinetic energy: | Solution of alcohol and water |
35. Which one of the following gases has the lowest density at room temperature? | H2 |
36. Which one of the following values of the R constant is not correct? | 1.987 cal K^-1 mol^-1 |
37. Which of the following equations is for real gas? | PV = nRT |
38. If T, M, V, and P are gas constant temperature, molar mass, volume, and pressure, then density is given by: | PM/RT |
39. General gas equation can be derived by combining: | Boyle’s law, Charles’s law, and Avogadro’s law |
40. The value of general gas constant R is derived from: | Avogadro’s, Coming, and Maxwell’s law |
Question | Answer |
24. Naphthalene, iodine, and NH4 can: | Sublime |
26. In a better method, the process of sublimation is carried out in a: | Cold finger |
27. Which of the following substances is not a sublime material? | Potash alum |
28. Which of the following methods is used to obtain iodine present in the water? | Sublimation |
29. Solvent extraction method is a particularly useful technique for separation when the product to be separated is: | Volatile and thermally unstable |
30. Solvent extraction is an unstable process and it is controlled by: | Distribution law |
31. The most common laboratory example of solvent extraction is: | Ether extraction |
32. The other name for distribution law is: | Partition law |
33. In CCl4 solvent, I2 shows: | Purple colour |
34. The comparative rates at which solutes move in paper chromatography depend on: | Rf value of the solute |
35. To help diagnose illness, doctors often need to know which amino acids are present in urine or blood, which method is commonly called: | Chromatography |
36. The components of which mixture can be separated by chromatography? | Blue and red inks |
37. In chromatography, the point at which solvent maximum rises is called: | Solvent front |
38. Chromatography involves the distribution of a solute between: | A stationary and a mobile phase |
39. Chromatography in which stationary phase is a liquid is called: | Partition chromatography |
40. Chromatography in which stationary phase is a solid is called: | Adsorption chromatography |
1. Which of the following is the simplest form of matter? | Gaseous state |
2. The movement of gas molecules from a region of high pressure to vacuum is called: | Diffusion |
3. All gases can be compressed by: | Increasing pressure |
4. Gases exert pressure on walls of the container because the gas molecules: | Collide with the walls of the container |
5. Gases of air always remain in random motion and do not settle due to: | Elastic collision of gas molecules |
6. The rate of diffusion of a gas is: | Inversely proportional to square root of its molecular mass |
7. In gases and liquids, temperature is the measure of: | Average translational kinetic energies of molecules |
8. In solids, the temperature is the measure of: | Vibrational kinetic energies |
9. Cooling happens under the Joule Thomson effect due to sudden: | All of the above |
10. They spread throughout the vessel: | Pressure is due to collision |
11. Pressure is due to: | Internal and external conditions |
12. Liquids are less common than: | Gases |
13. The intramolecular forces in gases are: | Very weak |
14. The relationships between volume of a given amount of gas and the prevailing conditions of temperature and pressure are: | Gas laws |
15. In Boyle’s law, which of the following pair remains constant: | Temperature and quantity of a gas |
16. In Boyle’s law, which of the following pair is variable: | Pressure and Volume |
17. For a gas obeying Boyle’s law, if pressure is doubled, the volume becomes: | One half |
18. Boyle’s law is represented as: | PV = k |
19. According to Boyle’s law, which parameters give a straight line parallel to the x-axis, when we plot a graph between: | P and 1/V |
20. Boyle’s law does not fail even: | Pressure is extremely high |
21. A graph between P and 1/V at constant temperature and number of moles of a gas meets the: | y-axis |
22. A graph between P and PV at constant temperature and number of moles is parallel to: | x-axis |
Question | Answer |
Which of the following is NOT an alcohol? | CH3-O-CH3 |
Fossil fuels consist of: | All of these |
Geological survey of Pakistan estimates about billion tons of coal in Pakistan: | 184 |
Major component of natural gas is: | Methane |
At present oil refineries in Pakistan are: | Four |
Cracking products are: | Alkanes and alkenes |
Types of cracking are: | All a, b, c |
Tetraethyl lead causes disease: | Respiratory |
The general formula of saturated alicyclic hydrocarbons is: | CnH2n |
Diversity of organic compounds in millions is: | Six |
General formula of carboxylic acids is: | RCOOH |
Linear geometry is present in: | sp |
Angle 120° is observed in molecules: | CH2=CH2 |
Preparation of vegetable ghee involves: | Hydrogenation |
Formula of chloroform is: | CHCl3 |
The presence of a double bond in a compound is the sign of: | Unsaturation |
Vinyl acetylene combines with HCl to form: | Chloroprene |
The addition of an unsymmetrical reagent to an unsymmetrical alkene is in accordance with the rule: | Markownikoff’s rule |
Synthetic rubber is made by polymerization of: | Butene |
β,β’-dichloroethyl sulphide is commonly known as: | Mustard gas |
When methane reacts with Cl2 in the presence of diffused light, the products obtained are? | Mixture of a, b, c |
Which one of the following gases is used for artificial ripening of fruits? | Ethyne |
Reaction of ethenes with KMnO4 gives: | Hydroxylation |
The branch of science dealing with structure, composition, and changes in matter and laws and principles which govern these changes is called: | Chemistry |
Smallest particle of an element which may or may not have independent existence is known as: | Atom |
Matter is defined as anything which occupies space and: | Mass |
The number of atoms present in a molecule determines its: | Atomicity |
When an electron is added to a unipositive ion, we get: | Neutral atom |
CO is an example of: | Stable molecule |
The diameter of atoms is of the order: | 2 x 10^-10 m |
Swedish chemist J. Berzelius determined: | Atomic mass |
Covalent compounds mostly exist in the form of: | Molecules |
Atoms and molecules can either gain or lose electrons, forming charged particles called: | Ions |
Metals tend to lose electrons, becoming: | Positively charged ions |
Non-metals tend to gain electrons, becoming: | Negatively charged ions |
First atomic theory was put forward by an English school teacher: | John Dalton |
Determination of atomic masses and invention of system of writing symbols was made by: | J. Berzelius |
Atoms can be evident by the use of electron microscope, field ionization microscope and: | X-rays |
The number of subatomic particles in atoms so far discovered is more than: | 110 |
C6H12O6 and C11H22O11 are: | Poly-atomic molecules |
Cl2, N2 and O2 are: | Diatomic molecules |
He, Ar and Ne are: | Mono-atomic molecules |
NH3, HCl, H2O, HI are: | Hetero-atomic molecules |
Haemoglobin contains nearly: | 10,000 atoms |
Haemoglobin is 63,000 times heavier than: | Hydrogen atom |
Molecules of high molecular weight usually greater than 10,000 are called: | Macromolecules |
Which statement about an atom is true? | Mass number can be equal to the atomic number |
Which statement about a molecule is incorrect? | Haemoglobin is a homo- atomic molecule |
A species having positive or negative charge is called: | Ion |
An ion bearing positive charge is called: | Cation |
An ion having negative charge is called: | Anion |
Formation of a cation is: | Exothermic process |
Anions are larger than their: | Parent atoms |
Any molecular species having positive charge is called: | Molecular ion |
Molecular ions are formed in an instrument called: | Mass spectrometer |
The mass of a molecular ion can be calculated from its: | m/e ratio |
The mass of one atom of an element compared with the mass of an atom of carbon taken as 12 is called: | Relative atomic mass |
Due to stability and abundance of carbon compounds, carbon is taken as: | Standard |
The masses of the atoms are extremely: | Large |
Relative atomic mass of O is: | 15.9994 amu |
Isotopes are sister atoms of the same element with similar chemical properties but different: | Atomic mass |
Isotopes of an element are recorded separately in: | Mass spectrometer |
Analytical chemistry is the science of: | Chemical characterization |
A complete chemical characterization of a compound must include: | Both (Qualitative analysis and Quantitative analysis) |
Estimation of Na in sea water is an example of: | Quantitative analysis |
Identification of a substance, determination of its structure, and quantitative analysis of its composition are the aspects covered by: | Modern analytical chemistry |
The detection of a functional group is called: | Qualitative analysis |
The sample being analyzed is called: | Analyte |
The solid remained on filter paper during filtration is called the: | Residue |
The filtration process is used to separate solid from: | Liquid |
The tip of the funnel should be 1 or 2 cm larger than the circle of the: | Filter paper |
The tip of the funnel should touch the side of the beaker in order to avoid: | Splashing |
Selection of filter paper depends upon sizes: | All of the above |
The liquid obtained after passing the mixture through filter paper is formed as: | Filtrate |
The apex angle of the folded filter paper is slightly greater than: | 60° |
Without proper suction, filtration is: | Slow process |
Fluted filter paper is used to: | Increase rate of filtration |
Gooch crucible is made of: | Porcelain |
Sintered glass is a porous material used for: | Filtration |
A suitable solvent should dissolve the maximum amount of solute at its boiling point and a minimum amount at: | Room temperature |
95% ethanol is called: | Rectified spirit |
The solution left after the formation of crystals is called: | Mother liquor |
Which one of the following substances is not used as a drying agent in desiccators? | NaCl (50%) |
Which one of the following substances is used as a decolorizing agent? | Animal charcoal |
Question | Answer |
In primary alkyl halides, the halogen atom is attached to a carbon which is attached to how many carbon atoms? | One |
The reactivity order of alkyl halides for a particular alkyl group is: | I > Br > Cl > F |
When CO2 is made to react with ethyl magnesium iodide, followed by hydrolysis, the product formed is: | Propanoic acid |
Grignard reagent is reactive due to: | The polarity of C-Mg bond |
SN2 reactions can be best carried out with: | Primary alkyl halide |
Elimination bimolecular reactions involve: | Second order kinetics |
For which mechanisms, the first step involved is the same: | E1 and SN1 |
Alkyl halides are considered to be very reactive compounds towards nucleophiles, because: | They have an electrophilic carbon and good leaving group |
The rate of E1 reaction depends upon: | The concentration of substrate |
Which one of the following is not a nucleophile? | BF3 |
General formula of alkyl halide is: | R-X |
General formula of alkyl halide is: | CnH2n+1X |
Best method of preparation of alkyl halide from alcohols is by its reaction with: | All |
Alkyl halides are reactive: | High |
SN2 reaction has order of reaction: | Second |
E2 has molecularity: | 2 |
The conversion of n-hexane into benzene by heating in the presence of Cr2O3 is called: | Aromatization |
Simplest aromatic compound is: | Benzene |
Ratio of carbon to hydrogen in aromatic compounds is: | High than alkanes |
Kekule structures contributed towards actual structure of benzene: | 60% |
Resonance energy of benzene is (in KJ mol-1): | 150 |
Benzene gives reactions generally: | Electrophilic substitution |
Which decolourises the colour of Br2? | (b) and (c) |
Which is symmetrical alkene? | (b) and (c) |
Free radical mechanism of halogenation of alkanes follow step: | All of these |
Alkanes have functional group: | No functional group |
Which is the more reactive? | Alkynes |
Acetylene can be converted into while passing through a Cu-tube at 300°C. | Benzene |
Odour of alkyne is: | Garlic like |
Alkene general formula: | CnH2n |
Alkyne is: | CH≡CH |
Alkanes are gases: | C1-C4 |
The benzene molecule contains: | Delocalized π electron charge |
Aromatic hydrocarbons are the derivatives of: | Benzene |
Which of the following acid can be used as a catalyst in Friedel Craft’s reactions? | HCl |
Benzene cannot undergo: | Addition reactions |
Amongst the following, the compound that can be most readily sulphonated is: | Toluene |
During nitration of benzene, the active nitrating agent is: | NO2+ |
Acylation of benzene to produce aliphatic aromatic ketones is known as: | Friedel Craft’s reaction |
Benzene reacts with Cl2 in sunlight to give the end product: | C6H6Cl6 |
Which of following is explosive? | Nitrobenzene |
Which compound is the most reactive one? | Ethyne |
Among the following, polycyclic compound is: | Naphthalene |
Benzene can be obtained from: | All |
The electrophile in aromatic sulphonation is: | SO3 |
Aromatic compounds burn with sooty flame cause: | They have high percentage of carbon |
Question | Answer |
The carbon of a carbonyl group is: | sp² hybridized |
Formalin is: | 40% solution of formaldehyde in water |
Which of the following will have the highest boiling point? | 2-Hexanone |
Ketones are prepared by the oxidation of: | Secondary alcohol |
Acetone reacts with HCN to form a cyanohydrin. It is an example of: | Nucleophilic addition |
Which of the following compounds will not give Iodoform test on treatment with I2/NaOH? | 3-Pentanone |
Which of the following compounds will react with Tollen’s reagent? | CH3COCH |
Cannizzaro’s reaction is not given by: | Acetaldehyde |
Which of the following reagent will react with both aldehyde and ketone? | Grignard’s reagent |
Aldehydes are oxidized to give: | Carboxylic acid |
Carboxyl compounds have functional group: | R-CH=O |
The homologous series of aldehydes and ketones have general formula: | CnH2O |
Formula of acetone is: | CH3COCH3 |
Reaction of Grignard’s reagent with formaldehyde gives: | Primary alcohol |
Reaction of Grignard’s reagent with aldehydes other than formaldehyde gives: | Secondary alcohol |
Reaction of Grignard’s reagent with ketones gives: | Tertiary alcohol |
Iodoform test is given by: | Acetaldehyde and methyl ketones |
Aldehydes and ketones can be prepared from alcohols by their: | Oxidation |
Common names of aldehydes are given by corresponding: | Carboxylic acid |
Cannizzaro’s reaction is type of reaction: | Self oxidation-Reduction reaction |
Acetic acid is manufactured by: | Fermentation |
Metal used in the preparation of Grignard’s reagent is: | Mg |
Reaction of Grignard’s reagent with CO2 gives: | Carboxylic acid |
Reaction of which with Grignard’s reagent gives primary alcohol: | Formaldehyde |
Primary carbon attaches with other hydrogen atoms directly: | At least one or more than it |
Which compound shows more hydrogen bonding? | C2H5OH |
Which compound shows maximum hydrogen bonding with water? | CH3OH |
Which compound is more soluble in water? | CH3OH |
Which compound will have the maximum repulsion with water? | CH4 |
Ethanol can be converted into ethanoic acid by: | Oxidation |
Which enzyme is not involved in the fermentation of starch? | Urease |
Which compound is called a universal solvent? | H2O |
Methyl alcohol is not used: | As a substitute for petrol |
Rectified spirit contains alcohol about: | 95% |
According to Lewis concept ethers behave as: | Base |
Phenols are derivatives of: | Benzene |
Alcohols are derivatives of: | Alkanes |
Derivative of water is: | All of these |
Dow’s method is used to prepare: | Phenol |
Which is not a property in ether: | High boiling point |
Methanol is prepared from CO and H2 using catalyst: | ZnO |
Taste of lower alcohols is: | Sweet |
Oxidation of tertiary alcohol gives: | Alkenes |
Alcohols can be distinguished using test: | Lucas |
Ethyl alcohol prepared during fermentation is pure: | 12% |
Question | Answer |
In which of these processes are small organic molecules made into macromolecules? | The polymerization of ethane |
Which of these polymers is an addition polymer? | Polystyrene |
Which of these polymers is a synthetic polymer? | Polyester |
Plastics are a pollution problem because many plastics: | Burn to produce toxic fumes |
The fiber which is made from acrylonitrile as monomer: | Acrylic fibre |
A polymeric substance that is formed in the liquid state and then hardened to a rigid solid is called a: | Plastic |
Vegetable oils are: | Glycerides of unsaturated fatty acids |
Which one of the following elements is not present in all proteins? | Sulphur |
Which one of the following is a water-soluble vitamin? | Ascorbic acid |
Which one of the following enzymes brings about the hydrolysis of fats? | Lypase |
The reaction between fat and NaOH is called: | Saponification |
Which one of the following statements about glucose and sucrose is incorrect? | Both are disaccharides |
Which behaves as an insulator for the animal’s body? | Fats |
The steroids of fungi and yeast are called: | Ergosterol |
An oil or fat with no double bond has an iodine number: | Zero |
Which property is not present in lipids? | Soluble in water |
Which is the derived lipid? | Vitamin-D |
Major food factors are: | All of these |
Factors affecting denaturation of proteins: | All of these |
The high molecular weight materials which yield on hydrolysis the amino acids is called: | Proteins |
Cement is a combination of mainly: | Calcareous and argillaceous |
Major component in cement is: | Lime |
Composition of clay in cement is: | 25% |
Pakistan in the beginning was a country: | Agrarian |
Which is not a nitrogenous fertilizer? | Calcium phosphate |
A carboxylic acid contains: | A hydroxyl and carbonyl group |
Which acid is used in the manufacture of synthetic fibre? | Acetic acid |
Which following derivative cannot be prepared directly from acetic acid? | Acetamide |
Which reagent is used to reduce a carboxylic group to an alcohol? | LiAlH4 |
The solution of which acid is used for seasoning of food? | Acetic acid |
Organic compounds X and Y react together to form organic compound Z. What types of compounds can X, Y, and Z be? | X: Alcohol, Y: Acid, Z: Ester |
An aqueous solution of an organic compound reacts with sodium carbonate to produce carbon dioxide gas. Which one of the following could be the organic compound? | CH3CH2COOH |
Which of the following is not a fatty acid? | Phthalic acid |
Acetamide is prepared by: | Heating ammonium acetate |
A carboxylic acid with one carboxyl group: | Monocarboxylic acid |
A compound containing a carboxyl group in them is called: | Carboxylic acids |
A carboxylic acid containing Ar group in it is called: | Aromatic carboxylic acid |
O-COOH is an example of carboxylic acid: | Aromatic carboxylic |
In preparation method of carboxylic acids from alkyl halide always carboxylic acid formed which have carbon atoms: | One more than in R-X |
Which is not a carboxylic acid with a pungent smell? | Ethanoic acid |
Carboxyl group has functional groups in it: | One |
Carboxylic acids react with acids releasing gas from it: | CO2 |
Active metals react with carboxylic acids releasing gas: | H2 |
Acetic acid reacts with PCl5 giving: | Acetyl chloride |
Question | Answer |
The branch of science dealing with structure, composition, and changes in matter and the laws and principles governing these changes is called? | Chemistry |
Smallest particle of an element which may or may not have independent existence is known as? | An atom |
Matter is defined as anything which occupies space and? | Mass |
The number of atoms present in a molecule determines its? | Atomicity |
When an electron is added to a unipositive ion we get? | Neutral atom |
CO is an example of? | Stable molecule |
The diameter of atoms is of the order? | 2 x 10⁻¹⁰ m |
Swedish chemist J. Berzelius determined? | Atomic mass |
Covalent compounds mostly exist in the form of? | Molecules |
Atoms and molecules can either gain or lose electrons, forming charged particles called? | Ions |
Metals tend to lose electrons, becoming? | Positively charged ions |
Non-metals tend to gain electrons, becoming? | Negatively charged ions |
First atomic theory was put forward by an English school teacher? | John Dalton |
Determination of atomic masses and invention of the system of writing symbols was made by? | Berzelius |
Atoms can be evident by the use of electron microscope, field ionization microscope, and? | X-rays |
The number of subatomic particles in atoms so far discovered is more than? | 100 |
C₂H₂O₄ and C₄H₄O₄ are? | Poly-atomic molecules |
Cl₂, N₂, and O₂ are? | Diatomic molecules |
He, Ar, and Ne are? | Mono-atomic molecules |
NH₃, HCl, H₂O, HI are? | Poly-atomic molecules |
The pH range of acid rain is? | Less than 5 |
Peroxyacetyl nitrate (PAN) is an irritant to human beings and it affects? | Eyes |
The range of UV-B is? | 280 to 320 nm |
A single chloride free radical can destroy how many ozone molecules? | 100000 |
Fungicides are the pesticides which? | Control the growth of fungus |
DDT is a? | Insecticide |
The main pollutant of leather tanneries in the wastewater is due to the salt of? | Chromium (VI) |
In purification of potable water, the coagulant used is? | Aluminium sulphate |
The temperature in the incineration process has a range? | 950 to 1300°C |
Newspaper can be recycled again and again by how many times? | 5 |
Chloroform is carcinogenic to? | Liver |
Which is used as a coagulant? | Ferric salts and Potash alum |
Water is purified by the process? | All of these |
BOD is the oxygen demand within how many days? | Five |
Factors affecting the quality of water? | DO, BOD, COD |
Contamination of water of tanning industries is due to? | Cr(VI) |
Forms of waste products? | All of these |
How many pesticides have been synthesized at present? | Ten thousand |
A single free chlorine radical can destroy ozone molecules up to? | 100000 |
Depletion of ozone is more during the month? | Sept-Nov |
Unit of ozone is? | Dobson |
Main cause of reducing smog is? | All of these |
Coal contains sulfur in it? | 1-6% |
Volcanoes produce SO₂? | 67% |
Reasons for pollution are? | All of these |
Question | Answer |
Which statement is true about order of reaction? | Order of reaction can only be determined by an experiment |
The unit of rate constant K is mole⁻¹ dm³ s⁻¹ for a chemical reaction, the order of reaction is? | 2 |
Hydrolysis of ethyl-acetate (ester) has order of reaction? | 2 |
If rate law of an equation is written as -dx/dt = k[A][B]²? | Reactant is decreasing with passage of time |
The example of a photochemical reaction is photosynthesis has order of reaction? | 0 |
Rate law of an equation is obtained? | Experimentally |
A pseudo uni-molecular reaction has order of reaction? | 1 |
A zero order reaction is one in which? | Rate is not affected by changing concentration of reactants |
The rate equation for a reaction is Rate = K[A]. What are units of K? | mol dm⁻³ s⁻¹ |
The unit of the rate constant is the same as that of rate of reaction in? | Zero order reaction |
Half life period of a first order reaction is independent of? | All of above |
If the rate of decay of radioactive isotope decreases from 200 cpm to 25 cpm after 24 hours, what is its half-life? | 8 hours |
The rate of reaction between two specific time intervals is called? | Average rate of reaction |
Dilatometer method is useful for the reaction that involve? | Small volume changes in solutions |
The rate of reaction? | Decreases as the reaction proceeds |
Keeping in view the size of atoms, which order is the correct one? | Cl < I |
Mark the correct statement. | Na⁺ is smaller than Na atom |
Mark the correct statement. | All the alkali metals are present in the same group |
Which statement is incorrect? | All the metals form acidic oxides |
Which statement is correct? | Hydrogen resembles in properties with I-A, VII-A and IV-A elements |
Mark the correct statement. | The ionization energy of calcium is higher than that of beryllium |
Mark the correct statement. | Electron affinity is a measure of energy released by removing an electron |
Mark the incorrect statement. | Metallic character remains the same down the group |
Mark the correct statement. | Melting points of halogens first increase and then decrease down the group |
Mark the correct statement. | Covalent character of metal halides increases from left to right in a period |
Modern Periodic Table is based upon periods function? | Atomic number |
Newland’s gave law? | Octaves law |
The element not known till Mendeleev tabulated his periodic table? | Germanium |
Which one was the problem associated with Mendeleev periodic table? | Grouping of alkali metals with coinage metals |
BOD is the oxygen demand within day(s)? | Five |
Question | Answer |
(A) is one molar NaCl solution and (B) is molal NaCl solution: | B is more concentrated than A |
A solution of sucrose is 34.2%. The volume of solution containing one mole of solute: | 1000 cm³ |
10g of NaOH has been dissolved per dm³ of solution. The molarity of solution is: | 0.25 M |
10g of NaOH has been dissolved per kg of solvent. The molality of solution is: | 0.25 m |
The sum of mole per cent of all the components of solution is always equal to: | 100 |
The ratio of moles of a particular component of solution to total moles of all components of solution is: | Mole fraction |
5g of glucose is dissolved for 100 cm³ of solution. The percentage of solution is: | 5% w/v |
Electrochemistry is concerned with the conversion of electrical energy into chemical energy in: | Electrolytic cell |
The conversion of chemical energy into electrical energy requires: | Both Galvanic cell and Voltaic cell |
Most metals are conductors of electricity because of the: | Relatively free movement of their electrons |
Metallic conduction is also called as: | Electronic conduction |
Electrolytes in the form of solution or in the fused state have the ability to conduct: | Ions |
Ionization is the process in which ionic compounds when fused or dissolved in water split up into charged particles called: | Ions |
Electrolysis is used for: | All of above |
In an electrolytic cell, the electrons flow from: | Anode to cathode |
When aqueous NaCl is electrolyzed, which of the following ions get discharged at anode: | Cl⁻ |
In electrolytic cells, the chemical changes may be: | Either spontaneous or non- spontaneous |
Which of the following cannot conduct electricity: | NaCl (fused) |
During electrolysis, the reaction that takes place at cathode is: | Reduction |
During electrolysis, electrons are: | Gained by cathode |
The function of salt bridge is: | To maintain electrical neutrality |
Which of the following yield both hydrogen and chlorine on electrolysis: | Electrolysis of aqueous NaCl |
Which of the following correctly describes the process occurring at the electrodes when molten NaCl is electrolyzed: | Oxidation at anode, reduction at cathode |
What are the products of electrolysis of aqueous sodium chloride at two electrodes: | Chlorine at anode and hydrogen at cathode |
Sodium can be obtained by: | Electrolysis of molten sodium chloride |
A cell in which electric current is produced as a result of spontaneous redox reaction is called: | Galvanic cell |
A cell which produces electrical current by an oxidation-reduction reaction is known as: | Voltaic cell |
Which of the following reactions occur at moderate rate: | Rusting of iron |
All reactions occur in: | Both a single step and a series of steps |
The rate determining step is the: | Slowest step |
Which of the following will affect the rate: | Rate determining step |
It is common observation that rates of chemical reactions differ: | Greatly |
Which of the following may affect the rate constant (K) for a reaction: | Change in temperature |
The change in concentration of reactant or product per unit time is called: | Rate of reaction |
Rate of a chemical reaction depends upon: | Number of fruitful collisions per second |
Question | Answer |
A reaction is reversible because: | Products are reactive |
What happens when a reaction is at equilibrium and more reactant is added: | Forward reaction rate is increased |
The rate of a chemical reaction is directly proportional to product of molar concentration of reacting substance. It is called: | Law of mass action |
A chemical reaction A ⇌ B is said to be in equilibrium when: | Rate of transformation of A to B is equal to B to A |
The rate of reaction: | Remains same as reaction proceeds |
Law of mass action was given by: | Guldberg and Waage |
In a chemical reaction equilibrium is said to have been established when: | Rate of opposing reactions are equal |
In the above equilibrium system, if the concentration of reactants at 25°C is increased, the value of Kc will: | Remains constant |
For the above reaction the relationship between Kc and Kp will be: | Kp = Kc(RT)^-1 |
The correct relation between Kc and Kp is: | Kp = Kc(RT)^Δn |
N₂O₄ ⇌ 2NO₂ 1 mol of N₂O₄ was decomposed according to given equation in 1dm³ container. At equilibrium x mole of N₂O₄ have dissociated. What is the value of Kc: | 4x² / (1-x) |
2NO ⇌ N₂ + O₂ The unit of Kc for this reaction will be: | No unit |
N₂ + 3H₂ ⇌ 2NH₃ The unit of Kc for this reaction will be: | mol⁻² dm⁶ |
For what value of Kc almost forward reaction is complete: | Kc = 10³ |
In a particular reaction for the value Kc = 1 x 10³⁰ which statement is correct: | Almost forward reaction is complete |
Almost forward reaction is complete when value of Kc is: | Very large |
If Kc of a reaction is very large, it indicates that equilibrium occurs: | At a high product concentration |
N₂O₄ ⇌ 2NO₂ For the above reaction, which of the following expression of Kc is correct: | Kc = [NO₂]² / [N₂O₄] |
In an exothermic reversible reaction increase in temperature shift the equilibrium to: | Reactant side |
A large value of K means that at equilibrium: | Less reactants and more products |
Every sample of matter with uniform properties and a fixed composition is called a: | Phase |
A solution is a homogeneous mixture of two or more kinds of different: | Ionic substances |
The substance which is present in large quantity is called a: | Solvent |
The substance which is present in small quantity is called as: | Solute |
Solutions containing relatively lower concentrations of solute are called: | Dilute solutions |
In which type of following solutions we don’t know the total volume of the solution: | Percentage weight/weight |
In which of the following solutions the total volume of solution may not be necessarily equal to sum of volumes of solute and solvent? | Percentage volume/volume |
The number of moles of solute dissolved per dm³ of the solution is called: | Molarity |
The number of moles of solute in 1000g (1 kg) of the solvent is called: | Molality |
As compared to molar solution, in the molal solution the quantity of solvent is: | Comparatively greater |
To calculate volume of the solvent, we need to know, the: | Mass of solute |
Molarity of pure water is: | 55.5 |
A solution of glucose is 10%. The volume to which 1g mole of it dissolved will be: | 1.8 dm³ |
Question | Answer |
The study of heat changes accompanying a chemical reaction is known as: | Thermochemistry |
If an endothermic reaction is allowed to take place very rapidly in air, the temperature of the surrounding air: | Decreases |
In endothermic reactions, the heat contents of the: | Products more than that of reactants |
The majority of reactions which give stable products are: | Exothermic |
It is noticed that energy in the form of heat is either evolved or absorbed as a result of a: | Chemical change |
In a chemical change, the energy in the form of heat will either be evolved or absorbed and this is called: | Heat of reaction |
The energy units in which heat changes usually expressed in SI-system are: | Joule |
The subject matter of first law of thermochemistry is based on: | First law of Thermodynamics |
A process which takes place on its own from a non-equilibrium state towards an equilibrium state is termed as: | Both Spontaneous and Natural process |
Which one of the following is not related to spontaneous process: | Artificial |
Neutralization of a strong acid with a strong base is: | Both Natural acid base reaction and Spontaneous acid base reaction |
When a piece of zinc is added to the copper sulphate solution, colour of solution disappear: | Blue |
The reaction of Zinc with copper sulphate solution is an example of: | Spontaneous redox reaction |
A reaction will also be called a spontaneous if: | It does not need energy to start with |
Burning of coal and hydrocarbon in air are examples of: | Both Spontaneous reaction and Natural reaction |
Some non-spontaneous processes can be made to take place by supplying energy to the system from: | All of above |
By state, we mean the: | Condition of a system |
When no work is done by the system: | The volume of system decreases |
When a system absorbs energy, the sign of ΔE is: | Positive |
Work is a: | Only function |
The real or imaginary surface separating the system from the surroundings is called: | Boundary |
One mole of oxygen confined in a cylinder fitted with a piston is an example of: | System |
Reaction between Zn and CuSO4 can be called a system under: | Observation |
By comparing both initial and final states of the system, we can describe the change taking place in the: | System |
A state function is a: | Macroscopic property |
Which one of the following is not a state function? | Heat |
The kinetic energy is due to: | All of above (Translational, Rotational, Vibrational movements) |
Potential energy accounts for: | All types of attractive forces present in system |
The total of all the possible kinds of energies of the system is called its: | Internal energy |
ΔE is a: | State function |
Heat is: | Not a property of the system |
Heat evolved or absorbed by the system is represented by a symbol: | q |
The SI unit of work is: | Joules |
The kind of work most commonly encountered in chemistry is: | Pressure volume work |
Internal energy of the system is an: | Extensive property |
The increase in internal energy of a system can result in: | Both Physical change and Chemical change |
Heat evolved by a system is given: | Negative sign |
Energy of universe remains constant. It is called: | First law of Thermodynamics |
First law of thermodynamics is represented as: | ΔE = q + w |
Which of the following statements is contrary to the first law of thermodynamics: | Continuous production of mechanical work without supplying equivalent amount of heat is possible |