If a $100 \ mL$ solution contains $X \ g$ of $Na_2CO_3$ and its concentration is $Y \ M$,then $X$ and $Y$ are respectively ...............

What volume (in $mL$) of $HCl$ solution containing $73 \ g$ per litre is required to completely neutralise sodium hydroxide solution,obtained by allowing $0.46 \ g$ of metallic sodium to act upon water?

What is the value of percent atom economy when an organic compound of formula weight $75 \ u$ is obtained from reactants having sum formula weight $225 \ u$?

$20 \ mL$ of methane is completely burnt using $50 \ mL$ of oxygen. The volume of the gas left after cooling to room temperature is (in $mL$)

The mass of a mixture containing $NaCl$ and $NaBr$ is $4.0 \ g$. If $Na$ is $30 \%$ of the total mixture,the composition of $NaCl$ in the mixture is (in $\%$)

$2.5 \ cm^{3}$ of $0.2 \ M \ H_{2}SO_{4}$ solution is diluted to $0.5 \ dm^{3}$. Find the normality of the diluted solution. (in $N$)