JEE Main Chemistry – Page 2

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.

1. Metal that can not be obtained by the electrolysis of its aqueous solution is
1) silver 2) copper 3) gold 4) potassium

2. The reaction between potassium and nitrogen produces
A. K3N B. KN3 C. KNO2 D. KNO3
1) A only 2) B only 3) a mixture of C and D 4) none of these

3. A solution of common salt containing dissolved carbon dioxide is saturated with ammonia. The product obtained is
1) (NH4)2 CO3 2) Na2 CO3 3) NH4 HCO3 4) NaHCO3

4. Which of the following hydroxide has low solubility product in aqueous solutions
1) NaOH 2) Mg(OH)2 3) KOH 4) Ca(OH)2

5. Magnesium cannot be obtained by chemical reduction using carbon. This is because
1) Carbon is more electropositive than magnesium
2) Carbon is a very weak reducing agent
3) Carbon reacts with magnesium to form carbides
4) Carbon does not react with magnesium

6. MgCl2.6H2O on heating forms ‘X’ and finally transforms to ‘Y’ on strong heating. ‘X’ and ‘Y’ are respectively
1) Mg(OH)Cl, MgO 2) MgO, Mg(OH)2
3) MgO, Mg(OH)Cl 4) Mg(OH)2, Mg(OH)Cl

7. Assertion(A): Mg2+ ions are precipitated by adding NH4OH in the presence of NH4Cl Reason(R): Mg(OH)2 is less soluble in water
1) A and R are true, R properly explain A
2) 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

8. Anhydrous aluminium chloride is covalent. But it is dissolved in water and hydrated ions are formed. This is due to the fact that
1) aluminium is trivalent
2) water is polar
3) lattice energy is high with Al3+
4) hydration energy is high with Al3+

9. The distance between two adjacent carbon atoms is graphite is ‘x’pm and between two adjacent layers is ‘y’pm. The ratio of ‘x’ and
‘y’ is about
1) 1 : 1 2) 2 : 5 3) 2 : 1 4) 4 : 5

10. Read the following statements :
(A) CCl4 does not undergo hydrolysis
(B) Carbon is easily attacked by fluorine
(C) PbCl4 is a good oxidising agent
(D) Carborandum is a covalent solid Number of correct statement in the above list is
1) only 1 2) two 3) three 4) all

11. Carbon dioxide Silicon dioxide
1. Gas at room 1. Solid at room temperature temperature
2. Has sp hybridisation 2. Has sp3 of central atom hybridisation of
central atom
3. Has only double 3. Has only single bond bond
4. Molecular formula 4. Molecular is CO2 formula is SiO2
Wrong in the differences of the table is
1) 1 2) 2 3) 3 4) 4

12. Acid used for making permanent marking on the glass surface is
1) HF 2) HNO3 3) H2SO4 4) HClO4

13. Number of ‘O’ atoms around ‘N’ of N2O3 and N2O5 are n1 and n2.
Number of ‘O’ atoms around ‘P’ of P4O6 and P4O10 are n3 and n4.
These numbers are respectively
1) 2, 3, 4 and 5 2) 2, 3, 3 and 4
3) 1, 2, 3 and 4 4) 3, 5, 6 and 10

14. Correct order of volatility of hydrides of group 15 elements is
1) NH3 > PH3 > AsH3 > SbH3
2) PH3 > AsH3 > SbH3 > NH3
3) PH3 > AsH3 > NH3 > SbH3
4) PH3 > NH3 > AsH3 > SbH3

15. Gas ‘A’ is passed through water to form a saturated solution. This solution gives a white precipitate with silver nitrate. This solution dissolves magnesium, liberating a colourless gas ‘B’. ‘A’ and ‘B’ are respectively
1) Cl2, CO2
2) Cl2, H2
3) CO2, Cl2
4) H2, Cl2

16. A mixture of noble gases can be separated by
1) adsorption and desorption of charcoal
2) liquification process
3) electrolysis of their molten fluorides
4) reaction with steam

17. Super phosphate of lime contains the pair of ions
1) SO2-4 , HPO2-4 2) HSO-4 , HPO-4 3) SO2-4, H2PO-4 4) HSO-4, PO3-4

18. Which of the following is same for H2 and D2
1) bond length 2) bond energy
3) rate of diffusion 4) rate of reaction

19. Regarding chromium peroxide CrO5, which of the following is false
1) oxidation state of Cr is +10
2) it is blue coloured
3) it has two peroxy bonds
4) it is stable in ether

20. ‘X’ is a colourless oxide of nitrogen which on exposure to air gives brown coloured ‘Y’. If ‘X’ and ‘Y’ are both gases at room
temperature, their nature
1) X is paramagnetic and Y is diamagnetic
2) Y is paramagnetic and X is diamagnetic
3) both X and Y are diamagnetic
4) both X and Y are paramagnetic

21. Structure of XeF4 molecule and bond angle are respectively
1) tetrahedral, 109.5o 2) trigonal, 120o
3) square planar, 90o 4) octahedral, 90o

22. Oxyacid of sulphur that has persulpide linkage
1) H2SO3 2) H2SO4 3) H2S2O7 4) H2S3O6

23. Aqueous solution of which of the following acts as bleaching agent
1) NCl3 2) PCl3 3) NF3 4) PCl5

KEY
1)4 2)4 3)1 4)2 5)3 6)1 7)4 8)4 9)2 10)4 11)4 12)1 13)2 14)3 15)2 16)1 17)3 18)1 19)1 20)4 21)3 22)4 23)1

JEE Main Physical Chemistry Model Questions with Key

JEE Main Chemistry Practice Questions and Answers