The percentage composition of carbon by mole in methane is :

• 20%

• 25%

• 75%

• 80%

The strength of 11.2 volume solution of H₂O₂ is: [Given that molar mass of H=1 g mol^–1 and O=16 g mol^–1]

• 1.7%

• 34%

• 13.6%

• 3.4%

At 300k and 1 atmospheric pressure 10ml of a hydrocarbon required 55mL of O₂ for complete combustion and 40mL of CO₂ is formed. The formula of the hydrocarbon is:

• C₄H₆

• C₄H₇Cl

• C₄H₈

• C₄H₁₀

For a reaction, N₂ (g) + 3H₂ (g) → 2NH₃ (g); Identify dihydrogen (H₂) as a limiting reagent in the following reaction mixtures.

• 35 gm of N₂ + 8 gm of H₂

• 28 gm of N₂ + 6 gm of H₂

• 56 gm of N₂ + 10 gm of H₂

• 14 gm of N₂ + 4 gm of H₂

Liquid ‘M’ and liquid ‘N’ form an ideal solution. The vapour pressures of pure liquids ‘M’ and ‘N’ are 450 and 700mm Hg, respectively, at the same temperature. Then correct statement is:

(x_M = Mole fraction of 'M' is solution; x_N = Mole fraction of 'N' in solution; y_M = Mole fraction of 'M' in vapour phase; y_N = Mole fraction of 'N' in vapour phase)

• $\frac{{\mathrm{x}}_{\mathrm{M}}}{{\mathrm{x}}_{\mathrm{N}}} < \frac{{\mathrm{y}}_{\mathrm{M}}}{{\mathrm{y}}_{\mathrm{N}}}$

• $\frac{{\mathrm{x}}_{\mathrm{M}}}{{\mathrm{x}}_{\mathrm{N}}} = \frac{{\mathrm{y}}_{\mathrm{M}}}{{\mathrm{y}}_{\mathrm{N}}}$

• $\frac{{\mathrm{x}}_{\mathrm{M}}}{{\mathrm{x}}_{\mathrm{N}}} > \frac{{\mathrm{y}}_{\mathrm{M}}}{{\mathrm{y}}_{\mathrm{N}}}$

• (x_M - y_M) < (x_N - y_N)

Equal moles of hydrogen and oxygen gases are placed in a container with a pin-hole through which both can escape. What fraction of the oxygen escapes in the time required for one-half of the hydrogen to escape?

• 1/4

• 3/8

• 1/2

• 1/2

257.

Equal masses of H₂, O₂ and methane have been taken in a container of volume V at temperature 27⁰ C in identical conditions. The ratio of the volumes of gases H₂ : O₂: CH₄ would be 

• 8:16:1

• 16:8:1

• 16:1:2

• 16:1:2

When 22.4 L of H₂ (g) is mixed with 11.2 L of Cl₂ (g), each of at STP, the moles of HCl (g) formed is equal to

• 1 mole of HCl (g)

• 2 moles of HCl (g)

• 0.5 mole of (g) 

• 0.5 mole of (g) 

1.0 g of magnesium is burnt with 0.56 g of O₂ in a closed vessel. Which reactant is left in excess and how much?

• Mg, 0.16 g

• O₂, 0.16 g

• Mg, 0.44 g

• Mg, 0.44 g

In the Kjeldahl's method for estimation of nitrogen present in a soil sample, ammonia evolved from 0.75 g of sample neutralised 10 mL of 1 M H₂SO₄.The percentage of nitrogen in the soil is

• 37.33

• 45.33

• 35.33

• 35.33