How much of $NaOH$ is required to neutralize $1500 \ cm^3$ of $0.1 \ N \ HCl$ (At. wt. of $Na = 23$)?

The normality of orthophosphoric acid having purity of $70\%$ by weight and specific gravity $1.54$ would be ............. $N$.

$A$ mixture of gases contains $H_2$ and $O_2$ gases in the ratio of $1 : 4$ $(w/w)$. What is the molar ratio of the two gases in the mixture?

Upon mixing $50.0 \ mL$ of $0.1 \ M$ lead nitrate solution with $50 \ mL$ of $0.05 \ M$ chromic sulphate solution,precipitation of lead sulphate takes place. How many moles of lead sulphate are formed and what is the molar concentration of chromic sulphate left in the solution?

How many millilitres of $6.0 \ M$ hydrochloric acid should be used to prepare $150 \ mL$ of a solution which is $0.30 \ M$ in hydrogen ion?

What mass of $95 \%$ pure $CaCO_3$ will be required to neutralise $50 \ mL$ of $0.5 \ M \ HCl$ solution according to the following reaction? (In $g$)
$CaCO_{3(s)} + 2HCl_{(aq)} \rightarrow CaCl_{2(aq)} + CO_{2(g)} + H_2O_{(l)}$
[Calculate up to the second decimal place]