A welding fuel gas contains carbon and hydrogen only. Burning a small sample of it in oxygen gives 3.38 g carbon dioxide, 0.690 g of water and no other products. A volume of 10.0 litre (Measured at STP) of this welding gas is found weigh `11.6 g`. Calculate
(i) empirical formula,
(ii) molar mass of the gas, and
(iii) molecular formula.

Explanation

To solve the problem step by step, we will determine the empirical formula, molar mass, and molecular formula of the welding fuel gas based on the given data.

### Step 1: Calculate the mass of carbon in the carbon dioxide produced.

Given:
- Mass of CO₂ = 3.38 g

To find the mass of carbon (C) in CO₂:
...