Using the data provided, find the value of equilibrium constant for the following reaction at $$298 \mathrm{~K}$$ and $$1 \mathrm{~atm}$$ pressure.
$$\begin{aligned} \mathrm{NO}(g)+\frac{1}{2} \mathrm{O}_2(g) \rightleftharpoons & \mathrm{NO}_2(g) \\ \Delta_f H \mathrm{Y}[\mathrm{NO}(g)] & =90.4 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ \Delta_f H \mathrm{Y}\left[\mathrm{NO}_2(g)\right] & =32.48 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ \Delta S Y a t ~298 \mathrm{~K} & =-70.8 \mathrm{~JK}^{-1} \mathrm{~mol}^{-1} \end{aligned}$$
$$[\operatorname{antilog}(0.50)=3162 \text { ] }$$
Calculate the pOH of 0.10 M HCl solution.
Which among the following pairs is not an acidic buffer?
Assertion (A) The colour of old lead paintings can be restored by washing them with a dilute solution of $$\mathrm{H}_2 \mathrm{O}_2$$.
Reason (R) Hydrogen peroxide reduces $$\mathrm{PbS}$$ to $$\mathrm{Pb}$$.