JEE Main Physical Chemistry Model Questions with Key

Here we are giving model practice questions from Physical Chemistry for JEE Main candidates. JEE Main is going to be conducted by IITs JEE Baord for admission into Engineering programmes in IITs and NITs along with several deemed universities and participating colleges.

1. Assertion (A) : Cupric copper is paramagnetic Reason (R) : Charge of one mole of cupric is two Faradays
1) Both A and R are true, R properly explains A
2) Both A and R are true, R does not explain A
3) A is true, but R is false
4) A is false, but R is true

2. In one of the Bohr’s hydrogen orbit electron revolving with a wavelength of 10A0. The kinetic energy of the electron is
1) 13.6 eV 2) 10.2 eV
3) 3.4 eV 4) 1.5 eV

3. If R is Rydberg constant the wave length of first line in Balmer series of hydrogen emission spectrum is

4. In order to fill all the electrons of chromium (Z=24), number of orbitals required per atom is
1) 12 2) 13 3) 15 4) 24

5. Bond length of HCl is 1.275A° and experimental dipolemoment is 1.03D. The percentage ionic character of HCl is approximately
1) 16.8 2) 50.2 3) 66.7 4) 92.4

6. Aluminum fluoride is more ionic than aluminum chloride. This is because
1) Al is trivalent
2) Al3+ has high polarisation ability
3) F– is small in size
4) Cl – is less polarised

7. The ratio of pure and hybrid orbitals used for bonding in ethylene molecule
1) 1 : 1 2) 1 : 3 3) 3 : 1 4) 3 : 2

8. Ionic, covalent, dative and hydrogen bonds are all present in
1) ammonium chloride
2) epsom salt
3) potassium ferricyanide
4) sodium cyanide

9. Observe the following combinations
A : AB3E – NH3 – Pyramidal
B : AB4E2 – XeF4 – square planar
C : AB4 – CCl4– tetrahedral
D : AB2E2 –SnCl2 – angular

1) A, B, D are correct
2) A, C, D, are correct
3) B, C, D are correct
4) A, B, C are correct.

10. A open vessel at 27°C is heated until 1/4th of the air in it has been expelled. Assuming that the volume of the vessel remains
same, the temperature at which the vessel was heated is
1) 127°C 2) 177°C 3) 427°C 4) 477°C

12. van der Waals’ constants ‘a’ in atm L2 mol–2 and ‘b’ in L mol –1 are given for four gases : a = 4.17 and b = 0.037 for NH3 a = 1.39 and b = 0.032 for N2 a = 1.35 and b = 0.032 for Ar a = 3.99 and b = 0.042 for CO2 The change of state will be relatively easy for the gas
1) NH3 2) N2 3) Ar 4) CO2

13. Mayer’s relation Cp – Cv = R, can be applied for noble gases. Then the molar heat capacities at constant pressure and at constant volume are respectively
1) 1.5 R and 2.5 R 2) 2.5 R and 3.5 R
3) 3.5 R and 4.5 R 4) 4.5 R and 5.5 R

14. Under similar condition, the liquid that has highest vapour pressure among the following is
1) Diethyl ether 2) Ethanol
3) Acetic acid 4) Water

15. Packing density in the case of metal with face centered cubic structure is
1) 73% 2) 68% 3) 52% 4) 43%

16. Select the correct among the following statements
A) Na2O has 4 : 8 coordination
B) ZnS has 4 : 4 coordination
C) NaCl has 6 : 6 coordination
D) CaF2 has 8 : 4 coordination

1) A, B, C 2) A, B, D
3) A, C, D 4) A, B, C, D

17. 17 grams of hydrogen peroxide is present in 560ml of aqueous solution. This solution is called
1) 10 volumes
2) 17 volumes
3) 20 volumes
4) 34 volumes

18. Molecular weight of a bivalent metal chloride is 136.4. Then equivalent weight of the metal is
1) 26.2 2) 32.7 3) 52.4 4) 65.4

19. Polythene is formed according to the equation nH2C = CH2 → (H2C – CH2)n. If 1000g of ethylene is taken, the mass of polythene formed is 1000
1) 1000g 2) g 3) 1000n g 4)ngn

20. An oxide of metal (M) has mass of oxygen 40%. If the atomic weight of M is 24, the emperical formula of oxide is
1) M2O3 2) MO2 3) MO 4) M2O

21. 1024 molecules of a solute of molar mass 100 are dissolved in
1025 molecules of solvent of molar mass 18. The mole fraction of
solute in the mixture is
1) 0.01 2) 0.09 3) 0.5 4) 0.8

22. 100ml of pure phosphine is decomposed to produce phosphorous solid and hydrogen. Under similar conditions of measurement,
the volume
1) increases by 50ml 2) decreases by 50ml
3) increases by 150ml 4) decreases by 150ml N

23. Hydrazoic acid is represented as || N– H. N The oxidation numbers of nitrogen are
1) –1, –1, –1 2) –1, –1, 0
3) 0, 0, –1 4) –1, –1, +1

24. The mass of natural water that has one mole of deuterium oxide (called heavy water) is
1) 1.2 kg 2) 12 kg
3) 120 kg 4)1200 kg

25. Weight percentage of chlorine in an alkali metal chloride is 48%. The atomic weight of the metal is likely
1) 56 2) 39 3)19 4)7

26. Analysis of an organic compound gas 40% of carbon and 6.6% hydrogen by weight. The chemical formula of the compound may be
1) HCOOCH3 2) OHC – CHO
3) CH3 – CH2OH 4) CH3 – CHO

28. Regarding oxidation numbers, which of the following is false
1) Oxidation number of metal in metal carbonyl is zero
2) Oxidation number of oxygen in a super oxide is fractional
3) Fluorine exhibits –1 oxidation state
4) The sum of oxidation number of all atoms in an ion is equal to charge of ion

29. PbS + H2O2 → PbSO4 + H2O
In the balance equation of the above reaction, number of electrons transferred from each molecule of H2O2 to lead sulphide is
1) 1 2) 2 3) 4 4) 8

30. 2 grams of a mixture of Na2CO3 and NaHCO3 on strong heating has suffered a mass loss of 0.62 gram. Percent weight of Na2CO3 in the given mixture is
1) 16 2) 24 3) 32 4) 50.

KEY: 1) 2 2) 4 3) 3 4) 3 5) 1 6) 3 7) 1 8) 2 9) 4 10) 1 11) 3 12) 1 13) 3 14) 1 15) 1 16) 4 17) 1 18) 2 19) 1 20) 3 21) 2 22) 1 23) 3 24) 3 25) 2 26) 1 27) 3 28) 1 29) 2 30) 1.

IIT – JEE Chemistry Practice Questions

IIT JEE Important Questions

1. Among the following ions, the pπ and dπ overlap will be present in
A) SO3 B) SO42- C) CO32- D) NO3 –

2. Which of the following molecules have unequal bond length?
A) NF3 B) SF4 C) SF6 D) PF5

3. The sizes of the following hydrated ions are in the order
A) Li+ < Na+ < K+ B) K+ < Li+ < Na+ C) K+ < Na+ < Li+ D) Ca2+ > Sr2+> Ba2+

4. Which of the oxides reacts with both, an acid and alkali, is
A) ZnO B) SnO2 C) Al2O3 D) NO

5. Which of the following species are isoelectronic isoelectronic
with NH4+
A) N3– B) O2– C) S2– D) Al3+

6. Which of the following hydrides are ionic?
A) CaH2 B) BaH2 C) SrH2 D) BeH2

7. Which of the following hydroxide is soluble in water?
A) Be(OH)2 B) Mg(OH)2 C) Ca(OH)2 D) Ba(OH)2

8. Which of the following are correct?
A) Magnesium with dil. HNO3 produces hydrogen
B) H2O2 bleaches by oxidation
C) H2O2 reduces KMnO4 only in alkaline medium
D) The position of hydrogen is not fixed in periodic table

9. If temperature of a gas is raised, which of the following would be true?
A) Fraction of the molecules possessing most probable velocity will increase
B) Fraction of the molecules possessing most probable velocity will decrease
C) Fraction possessing very low velocity will decrease
D) Fraction possessing very high velocity will increase

10. The pairs with identical values of magnetic moments
A) Zn2+, Cu+ B) Co2+, Ni2+ C) Mn4+, Co2+ D) Mg2+, Sc+

11. In the following reactions, hybridization of the underlined atom is affected
A) PCl 5 (solid) dissociates into PCl 4 + and PCl 6-
B) LiH reacts with AlH3 forming LiAlH4
C) NH3 is protonated
D) H3PO2 is heated forming PH3 and H3PO3

12. Relationship λ = h/p is true for
A) photons B) protons C) electrons D) positrons

13. Which of the following are postulates of kinetic theory of gases?
A) Gases consist of discrete molecules
B) Actual volume occupied by gas molecules (M/NA) times the volume of the container where M and NA represent molecular weight of gas and Avagadro’s number respectively
C) Molecules are in constant randomn motion and have constant kinetic energy at all temperature
D) No force of attraction or repulsion exists between gas molecules

14. Correct statements are
A) molar volume of every gas at STP is 22.4L
B) Under critical states compressibility factor is 1
C) All gases will have equal value of average KE at a given temperature.
D) at absolute zero, KE = 3/2 R.

15. Li does not resemble other alkali metals in the following properties
A) Li2CO3 decomposes into oxides
B) LiCl is predominantly covalent
C) Li3N is stable
D) LiF is insoluble in water

16. Mn+ + NaOH →coloured ppt. The coloured ppt is insoluble in excess of alkali. The metal ion may be
A) Fe2+ B) Fe3+ C) Cu2+ D) Zn2+

17. PbCl4 exists but PbBr4 and PbI4 do not because of
A) Br– and I– are large size ions
B) Br2 and I2 are electro negative
C) Chlorine is a gas
D) Br– and I– are reducing agents

18. From Maxwell Boltzmann distribution curve, the conclusions are
A) there is only a small number of molecules with very low velocities or very high velocities
B) largest number of molecules have a velocity corresponding to the maximum of the curve, which is most probable velocity
C) most probable velocity decreases on increasing temperature
D) distribution of the molecules in the given velocity range decreases on increasing temperature.

19. The molecules that will have dipole moment are
A) 2, 2-dimeethylpropane
B) cis-3-hexene
C) 2, 2, 3, 3-tetramethylbutane
D) trans-2-pentene

20. Which of the following statements is/ are incorrect regarding two organic compounds A and B which are stereoisomers?
A) They must be enantiomers
B) They must be geometrical isomers
C) They can be diastereomers
D) They can be meso compounds

21. Which are not isomers?
A) Methanol and methoxy methane
B) Ethyl alcohol and diethyl either
C) Acetone and acetaldehyde
D) Propionic acid and methyl acetate

22. About mesotartaric acid which of the following statements is/ are not correct?
A) It is optically inactive because it contains 2 asymmetric C atoms in its molecule
B) It can be separated into two optically active isomers
C) It cannot be separated into two optically active isomers
D) It is optically inactive due to external compensation

23. C4H10O formula will show
A) matamerism
B) functional isomerism
C) position isomerism
D) chain isomerism

24. Which of the following statements is/ are true about the quantum numbers n, l , m and s?
A) l gives an idea of the shape of the orbital
B) m gives the information of the energy of electron in a given
orbital
C) n gives the idea of the size of the orbital
D) s gives the direction of spin of electron in an orbital

25. Which of the following is correct under the same conditions of pressure and temperature?
A) Hydrogen diffuses 4 times faster than oxygen
B) Hydrogen diffuses 2.83 times faster than methane
C) Helium escapes at a rate 2 times as fast as methane does
D) Helium escapes at a rate 4 times as much as sluphur dioxide

26. Which of the following shows tautomerism?
A) C6H5OH
B) CH3NO2
C) C6H5CH2NO2
D) (CH3)3CNO2

27. Select incorrect statements
A) Molar volume of every gas at STP is 22.4L
B) Under critical states compressibility factor is 1
C) All gases will have equal value of average KE at given temperature.
D) At absolute zero, KE is 3/2 R.

28. Pick up the correct statement
A) II is more soluble than I in H2O
B) II is more soluble than III in H2O
C) II is less soluble than III in H2O
D) III is more soluble than I in H2O

29. Which are the species in which sulphur undergoes sp3 hybridisation?
A) SF4 B) SCl 2 C) SO42- D) H2S

KEY
1)AB 2)BD 3)CD 4)ABC 5) ABC 6)ABC 7) BCD 8) ABD 9) BCD 10)AD 11)AB 12)BC 13)AD 14) AC 15) ABC 16) ABC 17) AD 18) ABD 19)BD 20)AB 21)ABC 22) ABD 23) ABCD 24) ACD 25) ABCD 26) ABC 27) BD 28) ACD 29) BCD

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