Methylation of $10 \ g$ of benzene gave $9.2 \ g$ of toluene. Calculate the percentage yield of toluene $......$. (Nearest integer)

The volume of air needed for complete conversion of $100 \ cm^3$ of $NO$ to $NO_2$ will be (assuming $20 \%$ $O_2$ by volume in air).
$2 NO_{(g)} + O_{2(g)} \rightarrow 2 NO_{2(g)}$ (in $cm^3$)

The normality of $2 \ M$ sulphuric acid is: (in $N$)

What is the volume in $litres$ of the gas produced at $NTP$ by the reaction of $100 \ g$ of $CaC_2$ with water?
$CaC_2 + 2H_2O \rightarrow Ca(OH)_2 + C_2H_2$

When $5 \, mL$ of $N \, HCl$,$20 \, mL$ of $N/2 \, H_2SO_4$,and $30 \, mL$ of $N/3 \, HNO_3$ are mixed together and the volume is made up to $1 \, L$,the normality of the resulting solution is:

The concentration of a $100 \ mL$ solution containing $X \ g$ of $Na_2CO_3$ (molecular weight $= 106$) is $Y \ M$. The values of $X$ and $Y$ are respectively.