$KMnO_4$ reacts with $KI$ in basic medium to form $I_2$ and $MnO_2$. When $250 \ mL$ of $0.1 \ M \ KI$ solution is mixed with $250 \ mL$ of $0.02 \ M \ KMnO_4$ in basic medium, what is the number of moles of $I_2$ formed?

When $20 \ g$ of $CaCO_3$ is treated with $20 \ g$ of $HCl$,the mass of $CO_2$ formed would be: (in $g$)

What is the number of moles of water molecules required to prepare $n$ moles of methane from $n$ moles of methyl magnesium iodide?

$A$ reaction gas mixture contains $50 \%$,$30 \%$,and $20 \%$ of $A$,$B$,and $C$ by volume,respectively. The mixture undergoes the following reactions:
$1. A + 2B \rightarrow P_1$
$2. 4P_1 + 3C \rightarrow P_2$
$P_1$ and $P_2$ are two products of the reactions. Choose the correct answer if the reaction completes.

When $22.4 \ L$ of $H_{2(g)}$ is mixed with $11.2 \ L$ of $Cl_{2(g)}$,each at $S.T.P.$,the moles of $HCl_{(g)}$ formed is equal to

Production of iron in a blast furnace follows the following equation:
$Fe_{3}O_{4(s)} + 4CO_{(g)} \rightarrow 3Fe_{(s)} + 4CO_{2(g)}$
When $4.640 \ kg$ of $Fe_{3}O_{4}$ and $2.520 \ kg$ of $CO$ are allowed to react,the amount of iron (in $g$) produced is $....$
[Given: Molar Atomic mass $(g \ mol^{-1}): Fe = 56, O = 16, C = 12$]