Question

clicker question
which one is the strongest acid, h₂se, h₂s or h₂o?
a. h₂o
b. h₂s
c. h₂se
d. all three have the same acid strength.
e. i don’t really feel like responding right now.

Explanation:

For binary acids (like \(H_2O\), \(H_2S\), \(H_2Se\) which have the general formula \(H_nX\)), the acid - strength depends on the bond - strength. As we move down a group in the periodic table (O, S, Se are in group 16), the atomic size increases. Larger atoms (Se in this case compared to S and O) lead to longer and weaker \(H - X\) bonds. Weaker \(H - X\) bonds mean that the \(H^+\) ion is more easily released in solution. Since \(H - Se\) bond is weaker than \(H - S\) and \(H - O\) bonds (because Se is larger than S and O), \(H_2Se\) will release \(H^+\) more readily than \(H_2S\) and \(H_2O\).

Answer:

C. \(H_2Se\)