Give uses of $CO_{2}$.

Match the following:
| List-$I$ | List-$II$ |
| :--- | :--- |
| $A$. Carbon black | $I$. Electrodes in batteries |
| $B$. Graphite | $II$. Extraction of metals |
| $C$. Diamond | $III$. Abrasive |
| $D$. Activated charcoal | $IV$. Filler in automobile tyres |
| | $V$. Air conditioning system |

$A$ tetravalent element forms monoxide and dioxide with oxygen. When air is passed over the heated element $(1273 \ K)$,producer gas is obtained. The monoxide of the element is a powerful reducing agent and reduces ferric oxide to iron. Identify the element and write the formulas of its monoxide and dioxide. Write chemical equations for the formation of producer gas and the reduction of ferric oxide with the monoxide.

Which of the following is not a pseudohalide?

Give one method for industrial preparation and one for laboratory preparation of $CO$ and $CO_2$ each.

$SiCl_4$ on hydrolysis forms '$X$' and $HCl$. Compound '$X$' loses water at $1000^{\circ} C$ and gives '$Y$'. Compounds '$X$' and '$Y$' respectively are: