kaplan general chem

[SING2016]

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19. Which of the following is the strongest base?
A. NaCl
B. LiF
C. Na2S
D. KBr
E. BF3
can someone explain why the answer is C. I was using chads notes to answer the question. His notes say cations from group 1 and group 2 metals are negligible or neutral. Plus anions are usually basic Cl-, Br-, I-, NO3-, ClO4-, and ClO3- . Based of this why cant your answer be B, C, or E

 

[Likkriue]

E is an acid, because it's a Lewis acid, same with alcl3.
Anions of strong acids are negligible, I could have sworn chad went over this. So cl- br- etc etc are all negligible. LiF and na2s are the only two basic salts. Now why na2s is more basic? No idea, must be one of the periodic trends.

 

[gangazi]

HS- is weaker acid than HF, HCl, Hbr, so conjugate base should be the strongest

 

[rdub]

I would have chosen C simply because the anion has 2 minus charges (S--).