Gaseous benzene reacts with hyodrogen gas in presence of a nickel catalyst to form gaseous cyclohexane according to the reaction, 

C₆H₆ (g) + 3H₂ (g) → C₆H₁₂ (g)

A mixture of C₆H₆ and excess H₂ has a pressure of 60 mm of Hg in an unknown volume. After the gas had been passed over a nickel catalyst and all the benzene converted to cyclohexane, the pressure of the gas was 30 mm of Hg in the same volume at the same temperature. The fraction of C₆H₆ (by volume) present in the original volume is

• 1/3

• 1/4

• 1/5

• 1/6

The dissolution of Al(OH)₃ by a solution of NaOH results in the formation of

• [Al(H₂O)₄(OH)₂]⁺

• [Al(H₂O)₃(OH)₃]

• [Al(H₂O)₂(OH)₄]^-

• [Al(H₂O)₆(OH)₃

The molarity of NO₃^- in the solution after 2L of 3M AgNO₃ is mixed with 3L of 1M BaCl₂ is

• 1.2 M

• 1.8 M

• 0.5 M

• 0.4 M

2.76 g of silver carbonate on being strongly heated yields a residue weighing

• 3.45g 

• 3.0g

• 1.36g

• 2.16g

Which has the maximum number of molecules among the following?

• 44 g CO₂

• 48 g O₃

• 8g H₂

• 64g SO₂

1.5 g of CdCl₂ was found to contain 0.9 g of Cd. Calculate the atomic weight of Cd.

• 118

• 112

• 106.5

• 53.25

How many 'mL' of perhydrol is required to produce sufficient oxygen which can be used to completely convert 2 L of SO₂ gas to SO₃ gas?

• 10 mL

• 5 mL

• 20 mL

• 30 mL

The cubic unit cell of a metal (molar mass = 63.55 g mol^-1) has an edge length of 362 pm. Its density is 8. 92 g cm^-3. The type of unit cell is

• primitive

• face centred

• body centred

• end centred

The number of hydrogen atoms present in 25.6 g of sucrose (C₁₂H₂₂O₁₁) which has a molar mass of 342.3 g is

• 22 $\times$ 10²³

• 9.91 $\times$ 10²³

• 11 $\times$ 10²³

• 44 $\times$ 10²³ H atoms

30.

The number of formula units of calcium fluoride, CaF₂ present in 146.4 g of CaF₂ (the molar mass of CaF₂is 78.08 g/mol) is

• 1.129 $\times {10}^{24} {\mathrm{CaF}}_2$

• 1.146 $\times {10}^{24} {\mathrm{CaF}}_2$

• 7.808 $\times {10}^{24} {\mathrm{CaF}}_2$

• $1.877 \times {10}^{24} {\mathrm{CaF}}_2$