When ${CO_2}_{(g)}$ is passed over hot coke,it is reduced to ${CO}_{(g)}$. When $0.5 \, L$ of ${CO_2}_{(g)}$ is passed over hot coke,the total volume of the gas increases by $700 \, mL$ at $STP$. The composition of the resulting gaseous mixture is:

$417 \ g$ of $PCl_{5(s)}$ is kept in an open container where it reacts with moisture from air to form $POCl_{3(s)}$ and $HCl_{(g)}$. $A$ few hours later,the solid left in the container weighed only $395 \ g$. The percentage of $PCl_5$ converted to $POCl_3$ is: .............. $\%$ $(P = 31, Cl = 35.5, O = 16, H = 1)$

Concentrated aqueous sulphuric acid is $98\% \ H_2SO_4$ by mass and has a density of $1.80 \ g \ mL^{-1}$. The volume of acid required to make $1 \ L$ of $0.1 \ M \ H_2SO_4$ solution is ........ $mL$.

$19 \ g$ of a mixture containing $NaHCO_3$ and $Na_2CO_3$ on complete heating liberated $1.12 \ L$ of $CO_2$ at $STP$. The weight of the remaining solid was $15.9 \ g$. What is the weight (in $g$) of $Na_2CO_3$ in the mixture before heating?

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)

$16.8 \ L$ of a gas mixture containing $H_2$ and $O_2$ is formed at $NTP$ by the electrolysis of water. What is the mass of the electrolysed water in $g$?