HW problem 6C. 19 (f)

Acidity $K_{a}$
Basicity $K_{b}$
The Conjugate Seesaw $K_{a}\times K_{b}=K_{w}$

Eugene Chung 3F
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HW problem 6C. 19 (f)

Which is stronger acid and why?
(f) H2CO3 or H2GeO3.

I understand how higher electronegativity of C will result in it being the stronger acid, but I thought the acidity also depends on the bond length and that weaker (larger) bonds are stronger (Example in lecture was with H-F, H-Cl, H-Br with H-F being the weakest.)

Could anyone explain why the bond length doesn't matter in this question? is it because we're talking about an oxoacid?

Chem_Mod
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Re: HW problem 6C. 19 (f)

I would recommend drawing the structure. You will see that the hydrogens/protons being lost are not attached to C or Ge, but rather the oxygens. When you lose your hydrogen, you will have a negative charge, and you want that charge to be more evenly distributed to make the molecule more stable. Electronegative elements will contribute to that more stable distribution of charge.