Olete.in – MCQs, Mock Tests & Government Job Prep | NCERT Class 11 MCQ Questions for Class 11 Chemistry sets 3

Red phosphorus is chemically less reactive because

1. It does not contain P – P bonds
2. It dos not contain tetrahedral P4 molecules
3. It does not catch fire in air even upto 400°C
4. It has a polymeric structure

✅ Correct Answer: 4

Which of the following will not produce hydrogen gas?

1. Reaction between Fe and dil. HCl
2. Reaction between Zn and NaOH
3. Reaction between Zn and conc. H2SO4
4. Electrolysis of NaCl in Nelsons cell

✅ Correct Answer: 3

The structure of diBorane contains

1. Four 2c – 2e bonds and two 3c – 2e bonds
2. Two 2c – 2e bonds and two 3c – 2e bonds
3. Two 2c – 2e bonds and two 3c – 3e bonds
4. Four 2c – 2e bonds and four 3c – 2e bonds

✅ Correct Answer: 1

Which of the following oxidation states are most characteristic for lead and tin respectively?

1. 2, 2
2. 4, 2
3. 2, 4
4. 4, 4

✅ Correct Answer: 3

Among the C-X bond (where, X = Cl, Br, l) the correct decreasing order of bond energy is

1. C−I > C−Cl > C−Br
2. C−I > C−Br > C−Cl
3. C−Cl > C−Br > C−I
4. C−Br > C−Cl > C−I

✅ Correct Answer: 3

In the upper layers of atmosphere ozone is formed:

1. By action of electric discharge on oxygen molecule
2. By action of ultraviolet rays on oxygen molecule
3. By action of infrared rays on oxygen molecule
4. Due to sudden drops of pressure

✅ Correct Answer: 2

Oxygen gas can be prepared from solid KMnO4 by

1. Dissolving the solid in dil. HCl
2. Dissolving the solid in conc. H2SO4
3. Treating the solid with H2 gases
4. Strongly heating the solid

✅ Correct Answer: 4

Which is not the correct statement for Boron?

1. It exhibits Allotropy
2. It exists in both crystalline and Amorphous form
3. It forms solid chlorides
4. It forms volatile hydrides.

✅ Correct Answer: 3

When excess of Kl is added to copper sulphate solution:

1. Cuprous iodide is formed
2. l2 is liberated
3. Potassium iodide is oxidized
4. All

✅ Correct Answer: 4

Which of the following statements regarding ozone is not correct?

1. The oxygen-oxygen bond length in ozone is identical with that of molecular oxygen
2. The ozone is response hybrid of two structures
3. The ozone molecule is angular in shape
4. Ozone is used as a germicide and disinfectant for the purification of air.

✅ Correct Answer: 1

K2[Hgl4] detect the ion/group

1. NH2
2. NO
3. NH2+
4. Cl–

✅ Correct Answer: 3

Which of the following has least covalent P−H bond?

1. PH+4
2. P2H+5
3. P2H2+6
4. PH3

✅ Correct Answer: 3

If Cl2 gas is passed in to aqueous solution of Kl containing some CCl4 and the mixture is shaken then:

1. Upper layer becomes violet
2. Lower layer becomes violet
3. Homogenous violet layer is formed
4. None of these

✅ Correct Answer: 1

Which of the statement is true for the above sequence of reactions?

1. Z is hydrogen
2. X is B2H6
3. Z and Y are F2 and B2H6 respectively
4. Z is Potassium Hydroxide

✅ Correct Answer: 3

Ammonia gas can be dried by

1. conc H2SO4
2. P2O5
3. CaCl2
4. Quick lime

✅ Correct Answer: 4

Inert gases such as helium behave like ideal gases over a wide range of temperature .However; they condense into the solid state at very low temperatures. It indicates that at very low temperature there is a

1. Weak attractive force between the atoms
2. Weak repulsive force b etween the atoms
3. Strong attractive force between the atoms
4. Strong repulsive attractive between the atoms

✅ Correct Answer: 3

In general, the Boron Trihaides act as

1. Strong reducing agent
2. Lewis Acids
3. Lewis Bases
4. Dehydrating Agents

✅ Correct Answer: 2

On heating ozone, its volume.

1. Increase to 1.5 times
2. Decreases to half
3. Remain uncharged
4. Becomes double

✅ Correct Answer: 1

In the compound of type ECl3, where E = B, P, As, or Bi, the angle Cl – E – Cl for different E are ion the order:

1. B > = P = As = Bi
2. B > P > As > Bi
3. B < P = As = Bi
4. B < P < As < Bi

✅ Correct Answer: 2

If two compounds have the same empirical formula but different molecular formula they must have

1. Different percentage composition
2. Different molecular weight
3. Same viscosity
4. Same vapour density

✅ Correct Answer: 2

Identify the chiral molecule among the following:

1. Isopropyl alcohol
2. 2-pentanol
3. 1-bromo 3-butene
4. Isobutyl alcohol

✅ Correct Answer: 4

0.0833mol of carbohydrate of empirical formula CH2O contain 1g of hydrogen. The molecular formula of the carbohydrate is

1. C5H10O5
2. C3H4O3
3. C12H22O11
4. C6H12O6

✅ Correct Answer: 4

The displacement of electrons in a multiple bond in the presence of attacking reagent is called

1. Inductive effect
2. Electromeric effect
3. Resonance
4. Hyper conjugation.

✅ Correct Answer: 2

Which of the following cannot be represented by resonance structures?

1. Dimethyl ether
2. Nitrate anion
3. Carboxylate anion
4. Toluene

✅ Correct Answer: 1

An organic compound which produces a bluish green coloured flame on heating in presence of copper is

1. Chlorobenzene
2. Benzaldehyde
3. Aniline
4. Benzoic acid

✅ Correct Answer: 4

Which one is strongest acid among following options?

1. CH2FCOOH
2. CH2ClCOOH
3. CHCl2COOH
4. CHF2COOH

✅ Correct Answer: 2

Insulin contains 3.4% sulphur. The minimum molecular weight of insulin is

1. 350
2. 470
3. 560
4. 940

✅ Correct Answer: 4

What is the correct IUPAC name of

1. 4-methoxy-2-nitrobenzaldehyde
2. 4-formyl-3-nitro anisole
3. 4-methoxy-6-nitrobenzaldehyde
4. 2-formyl-5-methoxy nitrobenzene

✅ Correct Answer: 1

59 g of an amide obtained from a carboxylic acid, RCOOH, liberated 17 g of ammonia upon heating with alkali. The acid is

1. Formic Acid
2. Acetic Acid
3. Benzoic Acid
4. Propionic Acid

✅ Correct Answer: 2

In the Dumas method, the nitrogen present in organic compound gets converted to

1. Sodium Cyanide
2. Gaseoue Ammonia
3. Dinitrogen Gas
4. Ammonium Sulphate

✅ Correct Answer: 3

0.0833mol of carbohydrate of empirical formula CH2O contain 1 g of hydrogen. The molecular formula of the carbohydrate is

1. C5H10O5
2. C3H4O3
3. C12H22O11
4. C6H12O6

✅ Correct Answer: 4

The compound MCQ Questions for Class 11 Chemistry Chapter 12 Organic Chemistry Some Basic Principles and Techniques with Answers 3 is known by which of the following names

1. Bicyclo-[2, 2, 2] octane
2. Bicyclo-[2, 2, 1] octane
3. Bicyclo-[1, 2, 1] octane
4. Bicyclo-[1, 1, 1] octane

✅ Correct Answer: 1

Which one of the following conformations of cyclohexane is chiral?

1. Twist boat
2. Rigid
3. Chair
4. Boat

✅ Correct Answer: 1

If 0.228 g of silver salt of dibasic acid gave a residue of 0.162 g of silver on ignition then molecular weight of the acid is

1. 70
2. 80
3. 90
4. 100

✅ Correct Answer: 3

If there is no rotation of plane polarized light by a compound in a specific solvent, thought to be chiral, it may mean that

1. The compound may be a racemic mixture
2. The compound is certainly a chiral
3. The compound is certainly meso
4. There is no compound in the solvent.

✅ Correct Answer: 3

Which element is estimated by Carius method

1. Carbon
2. Hydrogen
3. Halogen
4. Nitrogen

✅ Correct Answer: 3

Inductive effect involves

1. displacement of σ electrons
2. delocalization of π electrons
3. delocalization of σ-electrons
4. displacement of π-electrons

✅ Correct Answer: 1

A crystalline solid possess which one of the following property?

1. Irregularity
2. Non- symmetric
3. Perfect geometric pattern
4. non- stability

✅ Correct Answer: 3

Which of the following behaves both as a nucleophile and as an electrophile?

1. CH3C ≡ N
2. CH3OH
3. CH2 = CHCH3
4. CH3NH2

✅ Correct Answer: 1

A dibromo derivative of an alkane reacts with sodium metal to form an alicyclic hydrocarbon. The derivative is ______.

1. 2, 2-dibromobutane
2. 1, 1-dibromopropane
3. 1, 4-dibromobutane
4. 1, 2-dibromoethane

✅ Correct Answer: 3

The position of double bond in alkenes can be located by

1. Hydrogenation of oil
2. Ozonolysis
3. Photolysis
4. Hydration

✅ Correct Answer: 2

Nitrobenzene on reaction with conc. HNO3/H2SO4 at 80 – 100°C forms which one of the following products?

1. 1, 2-Dinitrobenzene
2. 1, 3-Dinitrobenzene
3. 1, 4-Dinitrobenzene
4. 1, 2, 4-Trinitrobenzene

✅ Correct Answer: 2

Some meta-directing substituents in aromatic substitution are given. Which one is most deactivating?

1. –C ≡ N
2. -SO3H
3. -COOH
4. -NO2

✅ Correct Answer: 4

Which of the following compounds will exhibit geometrical isomerism?

1. 1 – Phenyl – 2 – butene
2. 3 – Phenyl – 1 – butene
3. 2 – Phenyl – 1 butene
4. 1, 1 – Diphenyl – propene

✅ Correct Answer: 1

The order of decreasing reactivity towards an electrophilic reagent, for the following : (i) Benzene (ii) Toluene (iii) Chlorobenzene (iv) Phenol would be:

1. (i) > (ii) > (iii) > (iv)
2. (ii) > (iv) > (i) > (iii)
3. (iv) > (iii) > (ii) > (i)
4. (iv) > (ii) > (i) > (iii)

✅ Correct Answer: 4

Pure methane can be prepared by

1. Soda lime decarboxylation
2. Kolbes electrolytic method
3. Wurtz reaction
4. Reduction with H2

✅ Correct Answer: 1

Hydrocarbon containing following bond is most reactive

1. C ≡ C
2. C = C
3. C-C
4. All of these

✅ Correct Answer: 1

The compound C3H4 has a triple bond, which is indicated by its reaction with

1. Bromine water
2. Bayers reagent
3. Fehling solution
4. Ammonical silver nitrate

✅ Correct Answer: 4

The angle strain in cyclobutane is

1. 24°44
2. 29°16
3. 19°22
4. 9°44

✅ Correct Answer: 4

The first fraction obtained during the fractionation of petroleum is:

1. Gasoline
2. Diesel Oil
3. Hydrocarbon Gases
4. Kerosene Oil

✅ Correct Answer: 3

2 – Phenylpropene on acidic hydration gives

1. 2 – Phenyl – 2 – propanol
2. 2 – Phenyl – 1 – propanol
3. 3 – Phenyl – 1 – propanol
4. 1 – Phenyl – 2 – propanol

✅ Correct Answer: 1

The coal tar fraction which contains phenol is:

1. Heavy Oil
2. Light Oil
3. Middle Oil
4. Green Oil

✅ Correct Answer: 3

Which one of these is not true for benzene?

1. There are three carbon-carbon single bonds and three carbon-carbon double bonds.
2. Heat of hydrogenation of benzene is less than the theoretical value
3. It forms only one type of mono substituted product
4. The bond angle between carbon-carbon bonds is 120 Degree

✅ Correct Answer: 1

The catalyst used in Friedel – Crafts reaction is

1. Aluminium Chloride
2. Anhydrous Aluminium Chloride
3. Ferric Chloride
4. Copper

✅ Correct Answer: 2

Alkyl halides react with dialkyl copper reagents to give?

1. Alkanes
2. Alkenes
3. Hydrogen
4. Carbon

✅ Correct Answer: 1

The lowest alkene, that is capable of exhibiting geometrical isomerism is

1. Ethene
2. But – 1- ene
3. But – 2 – ene
4. Propane

✅ Correct Answer: 3

Presence of a nitro group in a benzene ring

1. Activates the ring towards electrophilic substitution
2. Renders the ring basic
3. Deactivates the ring towards nucleophilic substitution
4. Deactivates the ring towards electrophilic substitution

✅ Correct Answer: 4

The agricultural field that produces maximum methane gas into atmosphere is

1. Wheat field
2. Paddy field
3. Cotton field
4. Groundnut field

✅ Correct Answer: 3

Fluorosis, the bone disease, is caused by the presence of

1. Pesticides in water
2. Fluorides in water
3. Carbon monoxide in air
4. Sulphur dioxide in air

✅ Correct Answer: 2

The most harmful air pollutant produced by automobiles is

1. HNO3
2. NO
3. SO2
4. CO

✅ Correct Answer: 4

Which of the following is responsible for depletion of ozone layer in the upper strata of the atmosphere?

1. Polyhalogens
2. Ferrocene
3. Fullerencs
4. Freons

✅ Correct Answer: 4

Which of the following acts as a sink for CO?

1. Plants
2. Haemoglobin
3. Microorganisms present in the soil
4. Oceans

✅ Correct Answer: 3

Which is most harmful for life on globe?

1. Deforestation
2. Soil Erosion
3. Increasing Desert
4. Nuclear Fallout.

✅ Correct Answer: 4

One of the following is the chief source of water and soil pollution

1. Agro industry
2. Mining
3. Thermal power stations
4. All of these

✅ Correct Answer: 3

What is the indicator of pollution in water?

1. Amount of oxygen
2. Amount of hydrogen
3. Amount of BOD
4. Amount of nitrogen

✅ Correct Answer: 3

The false statement among the followings:

1. The average residence time of NO is one month.
2. Limestone acts as a sink for SOx.
3. SOx can be removed from flue gases by passing through a solution of citrate ions
4. Ammonia acts as a sink for NOx.

✅ Correct Answer: 4

A disease caused by eating fish contaminated by industrial waste, containing mercury compounds, is called as

1. Minamata disease
2. Brights disease
3. Hashimotos disease
4. Osteosclerosis

✅ Correct Answer: 1

Identify the wrong statement in the following:

1. Acid rain is mostly because of oxides of nitrogen and sulphur
2. Chlorofluorocarbons are responsible for ozone layer depltion
3. Greenhouse effect is responsible for global warming
4. Ozone layer does not permit infrared radiation from the sun to reach the earth.

✅ Correct Answer: 4

Synthesis of ethanal commercially from which of the following reagent is the part of green chemistry?

1. CH3CH2OH
2. CH2 = CH2
3. HC ≡ CH
4. All of these

✅ Correct Answer: 2

Which of the following is produced by a reaction of ultraviolet light?

1. CO2
2. SO2
3. O3
4. NO3

✅ Correct Answer: 3

Why certain parts of water bodies contain more number of algae?

1. Due to favorable environment
2. Due to run-off excess fertilizers
3. Due to lack of fertilizers
4. Due to water pollution

✅ Correct Answer: 2

The substance which is a primary pollutant?

1. H2SO4
2. CO
3. PAN
4. Aldehydes

✅ Correct Answer: 2

The volume of 2.8 g of carbon monoxide at 27°C and 0.0821 atm is

1. 30 L
2. 3 L
3. 0.3 L
4. 1.5 L

✅ Correct Answer: 1

In van der Waal equation of state of gas laws, the constant b is a measure of

1. Intermolecular collisions per unit volume
2. Intermolecular attraction
3. Volume occupied by the molecules
4. Intermolecular repulsions

✅ Correct Answer: 3

Which of the following statement is wrong for gases?

1. Gases do not have definite shape and volume
2. Volume of the gas is equal to the volume of the container confining the gas
3. Confined gas exert uniform pressure on the wall of the container in all directions
4. Mass of the gas cannot be determined by weighing a container in which it is contained

✅ Correct Answer: 4

The critical volumes of four gases A, B, C, D are respectively 0.025 L, 0.312 L, 0.245 L, 0.432 L, the gas with highest value of van der Wall constant b is

1. A
2. B
3. C
4. D

✅ Correct Answer: 4

The value of universal gas constant R depends on

1. Temperature of Gas
2. Volume of Gas
3. Number of Moles of Gas
4. Units of Volume,Temperature and Pressure

✅ Correct Answer: 4

A gas deviates from ideal behavior at a high pressure because its molecules:

1. Attract one another
2. Show the Tyndall Effect
3. Have kinetic energy
4. Are bound by covalent bonds

✅ Correct Answer: 1

The state of matter that shows the uniformity of behavior :

1. Solid Liquid
2. Liquid
3. Gas
4. None of the above

✅ Correct Answer: 3

If 20cm³ gas at 1 atm. is expanded to 50 cm³ at constant T, then what is the final pressure

1. 20 × 150
2. 50 × 120
3. 1 × 120 × 50
4. None of these

✅ Correct Answer: 1

How many of the know elements exist as gases at 25°C?

1. 9
2. 11
3. 12
4. 15

✅ Correct Answer: 2

The states of matter having no definite shape but definite volume:

1. Gas
2. Liquid
3. Solid
4. None of the above

✅ Correct Answer: 2

The rise or fall of a liquid within a tube of small bore is called:

1. Surface Tension
2. Capillary Action
3. Viscosity
4. Formation of Curvature

✅ Correct Answer: 2

The theory which explains that gases consist of molecules, which are in rapid option is known as

1. Daltons Atomic Theory
2. Bohrs Theory
3. Rutherfords Atomic Theory
4. Kinetic Molecular Theory

✅ Correct Answer: 4

Falling drop of water is spherical due to:

1. Hydrogen Bonding
2. Surface Tension
3. Capillary Action
4. Vlscosity

✅ Correct Answer: 2