At $T \ K$,$3 \ moles$ of hydrogen and $1 \ mole$ of $N_2$ are allowed to react to form ammonia. When $1 \ mole$ of ammonia is formed,the total pressure in the vessel is $15 \ atm$. The partial pressure of $N_2$ in the vessel (in $atm$) is (in $.5$)

$1.84 \ g$ of a mixture of $CaCO_3$ and $MgCO_3$ is strongly heated to get a residue of $0.96 \ g$. The percentage of $CaCO_3$ in the mixture is

What is the mass of $33.6 \ dm^3$ of methane gas at $S.T.P.$?

At sea level,the dry air mass percentage composition is given as nitrogen gas: $70.0$,oxygen gas: $27.0$,and argon gas: $3.0$. If the total pressure is $1.15 \ atm$,calculate the ratio of the following respectively:
$(i)$ partial pressure of nitrogen gas to partial pressure of oxygen gas
$(ii)$ partial pressure of oxygen gas to partial pressure of argon gas
(Given: Molar mass of $N_2$,$O_2$,and $Ar$ are $28, 32$,and $40 \ g \ mol^{-1}$ respectively)

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

Volume of $0.1 \, M$ $H_2SO_4$ required to neutralize $30 \, mL$ of $0.2 \, N$ $NaOH$ is......$mL$