If salicylic acid $(138 \text{ u})$ reacts with acetic anhydride $(102 \text{ u})$ to form aspirin $(180 \text{ u})$ and acetic acid $(60 \text{ u})$,calculate the percentage atom economy. (in $\%$)

When a certain amount of ethylene is combusted,$6226 \, kJ$ of heat is released. If its enthalpy of combustion is $1411 \, kJ \, mol^{-1}$,the number of oxygen atoms consumed in the process at $STP$ will be ............... $N_A$.

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

If the density of liquid $HCl$ is $1.17 \, g \, cm^{-3}$,then its molarity will be ...............

Volume of air needed for complete combustion of $10 \ L$ of $C_2H_4$ is :
$($Assume air contains $20\%$ of $O_2$ by volume$)$ (in $L$)

$LiOH$ reacts with $CO_2$ to form $Li_2CO_3$ (atomic mass of $Li = 7$). The amount of $CO_2$ (in $g$) consumed by $1\, g$ of $LiOH$ is closest to $....\, g$