Mole fraction of $O_2$ in $O_2$ and $O_3$ mixture is $0.25$. Hence percentage concentration $\left( \frac{w}{W} \% \right)$ of $O_2$ in the mixture is:

Substance $A_2B_{(g)}$ can undergo decomposition to form two sets of products. If the molar ratio of $A_{2(g)}$ to $A_{(g)}$ is $5 : 3$ in a set of product gases,then the energy involved in the decomposition of $1 \, \text{mole}$ of $A_2B_{(g)}$ is:
$A_2B_{(g)} \to A_{2(g)} + B_{(g)}; \Delta H^o = 40 \, \text{kJ/mol}$
$A_2B_{(g)} \to A_{(g)} + AB_{(g)}; \Delta H^o = 50 \, \text{kJ/mol}$

$A$ mixture of sodium oxide $(Na_2O)$ and calcium oxide $(CaO)$ is dissolved in water and saturated with excess carbon dioxide $(CO_2)$ gas. The resulting solution is $......$ It contains $.........$ :

At $300 \ K$ temperature,$20 \ g \ H_2$,$220 \ g \ CO_2$,and $140 \ g \ N_2$ are filled in a vessel having volume $2 \ L$. Find the total pressure in $bar$ unit and which gas is removed from the vessel so that pressure can be reduced by $50 \%$. $(R = 8.34 \times 10^{-2} \ L \ bar \ K^{-1} \ mol^{-1})$

What is the approximate volume occupied by $22.4 \, L$ of water vapor at $STP$ when it is condensed into liquid water?

At $T(K)$,a gaseous mixture contains $H_2$ and $O_2$. The total pressure of the mixture is $2 \ bar$. The partial pressure of $H_2$ is $1.778 \ bar$. What is the weight $(w/w)$ percentage of $H_2$ in the mixture?