UPSC NDA I 2024 General Ability Paper

Concept:Water gas is a fuel gas mixture obtained from the reaction of steam with hot carbon.Explanation:Water gas consists of carbon monoxide ($\mathrm{CO}$) and hydrogen ($\mathrm{H}_2$).It is produced by passing steam over red-hot coke (carbon).The chemical reaction is: $\mathrm{C} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{CO} + \mathrm{H}_2$.This mixture is used as a fuel and as a reducing agent in industry.It is also a key component in the production of syngas and synthetic fuels.Options containing $\mathrm{CO}_2$ or $\mathrm{H}_2\mathrm{O}$ are incorrect.$\mathrm{CO}_2$ and $\mathrm{H}_2$ do not form water gas; they are products of combustion.$\mathrm{CO}$ and $\mathrm{H}_2\mathrm{O}$ are the reactants, not the mixture.Thus, only $\mathrm{CO}$ and $\mathrm{H}_2$ form water gas.Answer:$\mathrm{CO}$ and $\mathrm{H}_2$ (Option B).