$X$ litre of carbon monoxide is present at $STP$. It is completely oxidized to $CO_2$. The volume of $CO_2$ formed is $11.207 \ L$. What is the value of $X$ in litres?

The chloride of a metal is $MCl_2$. The formula of its phosphate will be:

The combustion reaction of glucose is given as: (Molar mass of glucose = $180 \ g/mol$) $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O, \Delta H = -72 \ kcal$. The energy required for the production of $1.6 \ g$ of glucose is .......... $kcal$.

The number of chlorine atoms in $20 \, mL$ of chlorine gas at $STP$ is ..... $\times 10^{21}$. (Round off to the Nearest Integer).
[Assume chlorine is an ideal gas at $STP$,$R = 0.083 \, L \, bar \, mol^{-1} \, K^{-1}$,$N_{A} = 6.023 \times 10^{23}$]

For preparing a $0.1 \ N$ solution of a compound from its impure sample,where the percentage purity is known,the weight of the substance required will be:

Formation of polyethylene from calcium carbide takes place as follows:
$CaC_2 + 2H_2O \to Ca(OH)_2 + C_2H_2$
$C_2H_2 + H_2 \to C_2H_4$
$n(C_2H_4) \to (-CH_2-CH_2-)_n$
The amount of polyethylene obtained from $64.1 \ kg$ of $CaC_2$ is......$kg$.