Question

Enter the chemical formula of a binary molecular compound of hydrogen and a Group 6A element that can reasonably be expected to be more acidic in aqueous solution than H2S , e.g. have a larger Ka.

Answer 1

Answer:

H₂Se

Explanation:

A way of estimating the acidity of a weak acid is by analizing the stability of the formed anion. In this case, we should find a Group 6A element that in its anionic forms (HX⁻ and X⁻²) is more stable than HS⁻ and S⁻², thus it would be more acidic in aqueous solution.

The anionic forms of Se are more stable than the forms of S, similarly to how Br⁻ is more stable than Cl⁻.