Question

From the reaction, $P _{\text {(white) }} \rightarrow P _{\text {(red) }}=\Delta H =-18.4\, kJ$ it follows that:

• A. red P is readily formed from white P
• B. white P is readily formed from red P
• C. white P cannot be converted to red P
• D. white P can be converted in to red P and red P is more stable

Answer 1

Answer: (D)

$P _{\text {(white) }} \rightarrow P _{\text {(red) }}, \Delta H =-18.4\, kJ$
Here, The reaction has spontaneous process which means white Phosphorous $P_{(\text {white) }}$ can be converted to $P_{( red )}$
For this reaction $\Delta H$ is Negative, which indicates that reaction is exothermic.
$\therefore $ Energy of red $P$ is lesser than white $P$ and thus, red $P$ is more stable.