Question

Based on their molecular structure, why are these acids thes stronger of the two binary acids given?
HCl stronger than HF
HF stronger than H2O
H2Se stronger than H2S
Is this because of bond strength due to placement on the table of elements? thanks

Answer 1

When you go DOWN the periodic table the acidity increases as the size of the atom (the non-hydrogen atom) increases. As you go ACROSS the periodic table (from left to right), it's the electronegativity of the non-hydrogen atom. Thus HF<HCl<HBr<HI and H3N<H2O<HF.

Answer 2

Thank you so much for ALL your help. You make it so simple and easy to understand.