Calculate the maximum possible heat which can be released if a $4 \ L$ aqueous solution is to be formed by mixing appropriate volumes of $2 \ M$ $NaOH$ and $3 \ M$ $H_2SO_4$ solution. Given $\Delta H_{\text{neutralisation, SA/SB}} = -14 \ kcal/mol$.

Consider the following reaction:
$3 PbCl_2 + 2 (NH_4)_3 PO_4 \rightarrow Pb_3(PO_4)_2 + 6 NH_4 Cl$
If $72 \ mmol$ of $PbCl_2$ is mixed with $50 \ mmol$ of $(NH_4)_3 PO_4$,then the amount of $Pb_3(PO_4)_2$ formed is $......... \ mmol$. (nearest integer)

If the heat of combustion of methane is $-100 \ kJ/mol$,then calculate the heat evolved when $32 \ g$ of methane reacts with $32 \ g$ of oxygen. (in $kJ$)

$A$ mixture of $100 \ mmol$ of $Ca(OH)_2$ and $2 \ g$ of $Na_2SO_4$ was dissolved in water and the volume was made up to $100 \ mL$. The mass of $CaSO_4$ formed and the concentration of $OH^{-}$ in the resulting solution,respectively,are:
(Molar mass of $Ca(OH)_2$,$Na_2SO_4$ and $CaSO_4$ are $74$,$142$ and $136 \ g \ mol^{-1}$ respectively; $K_{sp}$ of $Ca(OH)_2$ is $5.5 \times 10^{-6}$)

When burning magnesium ribbon is introduced into a jar of oxygen,it produces

$1 \ g$ of sodium hydroxide was treated with $25 \ mL$ of $0.75 \ M \ HCl$ solution. The mass of sodium hydroxide left unreacted is equal to: