$A$ gaseous mixture contains $CH_4$ and $C_2H_6$ in equimolecular proportion. The weight of $2.24 \ L$ of this mixture at $S.T.P.$ is :- .............. $g$

Mass of $NaOH$ required for formation of $100 \ mL$ of its decimolar solution is .............. $g$.

The amount of $50\% \ (w/w)$ solution of hydrochloric acid required to react with $200 \ g$ of $CaCO_3$ would be (in $g$)

$X \ g$ of benzoic acid on reaction with aqueous $NaHCO_3$ releases $CO_2$ that occupies $11.2 \ L$ volume at $STP$. The value of $X$ is . . . . . . $g$.

At the same temperature and pressure,if the mass of $3 \ L$ of a hydrocarbon is equal to the mass of $3 \ L$ of $CO_2$,what is the molecular formula of the hydrocarbon?

Three substances $A$,$B$ and $C$ react to form $E$ and $D$ as shown: $2A + 3B + C \rightarrow 4D + 2E$. If the molar masses of $A, B, C$ and $D$ are $40, 30, 20$ and $15 \ g/mol$ respectively,and $570 \ g$ of a stoichiometric mixture of $A, B$ and $C$ is reacted,the maximum mass of $E$ obtained will be ............ $g$.