The volume (in $mL$) of $0.1\, N$ $NaOH$ required to neutralize $10\, mL$ of $0.1\, N$ phosphinic acid is........

When a $1.0 \, g$ mixture of $NaHCO_3$ and $Na_2CO_3$ is heated at $150^{\circ}C$,$112.0 \, mL$ of $CO_2$ is produced at $STP$. Calculate the percentage of $Na_2CO_3$ in the mixture. $(Na = 23, C = 12, O = 16)$

How many grams of residue is obtained by heating $2.76 \text{ g}$ of silver carbonate (in $\text{ g}$)? (Given: Molar mass of $C$, $O$ and $Ag$ are $12$, $16$ and $108 \text{ g mol}^{-1}$ respectively)

$1 \ g$ of a carbonate $(M_2CO_3)$ on treatment with excess $HCl$ produces $0.01 \ mol$ of $CO_2$. The molar mass of $M_2CO_3$ is $.......... \ g \ mol^{-1}$. (Nearest integer)

The amount of calcium oxide produced on heating $150 \ kg$ of limestone ($75 \%$ pure) is $........... \ kg$ $(Nearest \ integer)$. Given: Molar mass (in $g \ mol^{-1}$) of $Ca = 40, O = 16, C = 12$.

The molecular weight of a gas is $45$. Its density at $STP$ is