STD 12 -1. Solution and colligative properties — NEET STD 11 Science — Question

$4B(s) + 3O_2\,(g) \rightarrow 2B_2O_3\,(g)$  ; $E^o_{cell} = 1.433$ $volt$  What is molar entropy (in $J/K$) of oxygen gas

Given ${\left( {{\Delta _f}{H^o}} \right)_{{B_2}{O_3}}}\left( g \right) =  - 840\,\frac{{KJ}}{{mol}}$

${\left( {S_m^o} \right)_{{B_2}{O_3}}} \left( g \right) = 280J/K - mol$ 

${{(S_{m}^{o})}_{B}}\,\,\left( s \right)=10\,J/K-mol$

$A \to {\text{Product ;}}\,\, - \frac{{d[A]}}{{dt}} = {k_1}{[A]^o}$

$B \to {\text{Product ;}}\,\, - \frac{{d[B]}}{{dt}} = {k_2}{[B]}$

Units of $k_1$ and $k_2$ are expressed in terms of molarity $(M)$ and time $(sec^{-1})$ as