Question

H2 +1/2o2 =h2o delta(hf) of h2o vapour is

Answer 1

Answer:

ΔHf of H₂O of water is when water vapor as liquid is converted into vapor form(below boiling point at normal atmospheric pressure) after its relatively strong hydrogen bonds are broken by the energy taken from the surrounding (ambience).

Once, the required energy to break the hydrogen bond, the water from liquid form changes its phase to gaseous form.

This reaction takes place for each molecule of water and that is the significance of ΔHf of H₂O of water vapor.