Do you mean h, rather than H? h is Planck's constant, f would conventionally be frequency.
Hf is the element hafnium. A dense gray metal. HF is the compound hydrogen fluoride, a toxic, acidic gas.
HF is a weak acid.
Hf, reactants > Hf, products
HF molecules form hydrogen bonds.
Hydrogen fluoride, with the chemical formula HF, is a colorless gas that is the principal source of fluorine. The type of intermolecular forces that exist in HF are London forces, dipole-dipole.
Because of high value of hydration energy.
apexvs answer 3.4 x 10-5
copied-in question and answer
The Hreaction is the difference between Hf, products and Hf, reactants
No, it is not ionic. HF is covalent.
HF is hydrogen fluoride.
Hreaction = Hf, products - Hf, reactants
Hf is the element hafnium. A dense gray metal. HF is the compound hydrogen fluoride, a toxic, acidic gas.
hf is the energy of photons incident on the surface
^Hreaction = ^Hf, products - ^Hf, reactants Apex
Hreaction = Hf products - Hf reactants
where liquid Hf is used