AFNS Most Repeated Chemistry MCQs

QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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 goldMajority 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
QuestionAnswer
8. Rate of evaporation and rate of condensation at equilibrium:Become equal
19. At sea level and at 100°C the vapour pressure of760 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%
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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%
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
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
QuestionAnswer
(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
QuestionAnswer
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
QuestionAnswer
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

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