Moles of conc. $HNO_3$ required to oxidise one mole of sulphur is :
$S + 6HNO_3 \rightarrow H_2SO_4 + 6NO_2 + 2H_2O$

In the preparation of baking soda,what is the ratio of $H_2O$ and $CO_2$ used to react with $Na_2CO_3$ to form $NaHCO_3$?

$A$ 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.

How many moles of lead $(II)$ chloride will be formed from a reaction between $6.5 \ g$ of $PbO$ and $3.2 \ g$ of $HCl$?

What will be the volume of the mixture after the reaction? $litre$
$NH_3(4 \ litre) + HCl(1.5 \ litre) \to NH_4Cl(s)$

What is the approximate mass of the precipitate formed when $50 \text{ mL}$ of $16.9\%$ solution of $AgNO_3$ is mixed with $50 \text{ mL}$ of $7.45\%$ $KCl$ solution (in $\text{ g}$)? (Molar mass of $AgNO_3 = 169 \text{ g/mol}$, $KCl = 74.5 \text{ g/mol}$, $AgCl = 143.3 \text{ g/mol}$)