Question

How do you write the equation that represents the formation of `HF(g)`?

Answer 1

`1/2H_2(g) + 1/2F_2(g) rarr HF(g)` `;DeltaH_"rxn"=DeltaH_f^@`

Explanation:

The standard enthalpy of formation is defined as the enthalpy associated with the formation of one mole of substance from it elements in their standard states, under standard conditions.

Given this definition, `DeltaH_f^@` `HF` is the enthalpy associated with the following reaction:

`1/2H_2(g) + 1/2F_2(g) rarr HF(g)` `;DeltaH_"rxn"=DeltaH_f^@`