[chita]

Hi, I have some doubts about hydrides and acidity

Hydracids and acidity: HI>HBr>HCl>HF
2nd row and acidity: HF>H2O>NH3>CH4

What I think:

Hydracids
1) Bond strenght: H-F > H-Cl > H-Br > H-I
2) Electronegativity difference: heavier halogen -> less electronegative -> less polarized bond -> weaker bond -> easier dissociation
3) Coniugate base stability: (electron affinity) Cl^- > F^- > Br^- > I^-
More or less order of acidity explained

2nd row
1) Bond strenght: H-F > O-H > C-H > N-H
2) Electronegativity difference: H-F > O-H > N-H > C-H
3) Coniugate base stability: F^- > OH^- > NH2^- > CH3^-
This considerations don't explain the order

Where am I wrong?

Thanks