The number of moles of BaCO₃ which contains 1.5 moles of oxygen atoms is:

1. 0.5

2. 1

3. 3

4. 6.02 ×10²³

The oxide of metal contains 40% by mass of oxygen. The percentage of chlorine in the chloride of the metal is

1. 84.7

2. 74.7

3. 64.7

4. 44.7

The empirical formula of an organic compound containing carbon and hydrogen is CH₂. The mass of one litre of this organic gas at STP  is exactly equal to that of one litre of N₂ at STP. Therefore, the molecular formula of the organic gas is:

1. C₂H₄

2. C₃H₆

3. C₆H₁₂

4. C₄H₈

A sample of pure compound is found to have Na = 0.0887 mole, O = 0.132 mole, C = 2.65 × 10²² atoms.

The empirical formula of the compound is 

(1) Na₂CO₃

(2) Na₃O₂C₅

(3) ${\mathrm{Na}}_{0.0887}{0}_{0.132}{\mathrm{C}}_{2.65\times {10}^{22}}$

(4) NaCO

An organic compound containing C, H, and N gave the following on analysis: C = 40%, H = 13.3% and N = 46.67%. Its empirical formula would be:

1. CHN
2. C₂H₂N
3. CH₄N
4. C₂H₇N

An organic substance containing C, H, and O gave the following percentage composition :

C = 40.687%, H = 5.085% and O = 54.228%. The vapour density of this organic substance is 59.

The molecular formula of the compound will be:

1. C₄H₆O₄

2. C₄H₆O₂

3. C₄H₄O₂

4. None of the above

When a solution containing 4.77 gm. of NaCl is added to a solution of 5.77 gm. of AgNO₃, the weight of precipitated AgCl is -

(1) 11.70 gm.

(2) 9.70 gm.

(3) 4.86 gm.

(4) 2.86 gm.

At standard temperature and pressure (STP), the volume of oxygen required to completely combust 30 ml of acetylene under similar conditions is:

1. 100 ml

2. 75 ml

3. 50 ml

4. 25 ml

What is the volume (in litres) of oxygen at STP required for complete combustion of 32 g of CH₄

(1) 44.8

(2) 89.6

(3) 22.4

(4) 179.2

A mixture of gases contains H₂ and O₂ gases in the ratio of 1:4 (w/w). What is the molar

ratio of the two gases in the mixture?

1. 1:4             

2. 4:1             

3. 16:1               

4. 2:1