$\frac{1}{2}{P_4}(s) + 3C{l_2}(g) \to 2PC{l_3}(l)\,;$ $\Delta H=-635 \,kJ$
$PC{l_3}(l) + C{l_2}(g) \to PC{l_5}(s)\,;$ $\Delta H=-137\, kJ$
The value of heat of formation of $PCl_5$ is ......$kJ\,mol^{-1}$
$\mathrm{PCl}_{3}(l)+\mathrm{Cl}_{2}(\mathrm{g}) \rightarrow \mathrm{PCl}_{5}(\mathrm{s}) ; \Delta \mathrm{H}=-137\, \mathrm{kJ}$
On adding $\frac{1}{4} \mathrm{P}_{4}(\mathrm{s})+\frac{5}{2} \mathrm{Cl}_{2}(\mathrm{g}) \rightarrow \mathrm{PCl}_{5}(\mathrm{s}) ; \Delta \mathrm{H}=-454.5\, \mathrm{kJ}$
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Assertion $A :$- Carbon forms two important oxides $- CO$ and $CO _2 . CO$ is neutral whereas $CO _2$ is acidic in nature.
Reason $R :$- $CO _2$ can combine with water in a limited way to form carbonic acid, while $CO$ is sparingly soluble in water.
In the light of the above statements, choose the most appropriate answer from the options given below :-
Statement $I:$ According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in positive charges on the nucleus as there is no strong hold on the electron by the nucleus.
Statement $II:$ According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in principal quantum number.
In the light of the above statements, choose the most appropriate answer from the options given below: