According to strict IUPAC thermochemical conventions, which of the following elemental substances po — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

Standard states dictate $\Delta_f H^\circ = 0$ exclusively for pure elements in their most stable reference phase. Graphite, rhombic sulphur, and highly reactive white phosphorus are the accepted standards. For bromine, the standard is liquid $Br_2(l)$, not gaseous.