$A$ photon having a wavelength of $310 \ nm$ is used to break the bond of an $A_2$ molecule with a bond energy of $288 \ kJ \ mol^{-1}$. Calculate the percentage of the photon's energy that is converted into kinetic energy $(K.E.)$. [Given: $hc = 12400 \ eV \mathring{A}$,$1 \ eV/atom = 96 \ kJ/mol$]

The volume of $HCl$,containing $73 \ g \ L^{-1}$,required to completely neutralize $NaOH$ obtained by reacting $0.69 \ g$ of metallic sodium with water,is $........ mL$. (Nearest Integer) (Given: molar masses of $Na, Cl, O, H$ are $23, 35.5, 16$ and $1 \ g \ mol^{-1}$ respectively)

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:
$A_2B_{(g)} \to A_{2(g)} + B_{(g)}; \Delta H^o = 40 \, \text{kJ/mol}$
$A_2B_{(g)} \to A_{(g)} + AB_{(g)}; \Delta H^o = 50 \, \text{kJ/mol}$

In a $20\%$ aqueous solution of $H_2O_2$,the mole fraction of water is $.......$.

When a jar containing a gaseous mixture of equal volumes of $CO_2$ and $H_2$ is placed in a solution of sodium hydroxide,the solution level will:

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