Question

Standard enthalpy of formation $\left(\Delta H_f\right)$ of which of the following is zero at ${25}^{0}C$ ?

• A. White phosphorous
• B. Red phosphorous
• C. Red lead $\left(P{b}_3{O}_4\right)$
• D. $H^{+}\left(g\right)$

Answer 1

The correct option is A White phosphorous

White phosphors is the elemental form of phosphorus for which enthalpy of formation is zero, while, $H^{+}$ and $P{b}_3{O}_4$ are not elemental forms.