Question

1. Classify the following compounds, as used in aqueous chemistry. That is if thrown in water what do you get. The following is a list of possibilities, for each classification. There may be more that I haven’t thought of. • Possibilites. (quite often you will have more than one classification possible for one compound) Strong Acid (SA) Weak acid (WA) Soluble salt (SS) Strong Base (SB) Weak Base (WB) Slightly soluble salt (IS) Diprotic Acid (DA) Diprotic base (DB) Triprotic acid (TA) Triprotic base (TP)

KH₂PO₄

HO₂CCHCHCO₂H

HOCH₂CH₂NH₂

K₂HPO₄

Hg₂(CN)₂

Answer 1

KH₂PO₄ => It is a solt of ammonium. But since there are two ionisable H+ ions in the molecule, the compound is slighly acidic. Hence it is a weak triprotic acid as well as a salt.

HO₂CCHCHCO₂H => it has two ionisable H+ ions from the COOH group. Hence, the compound is a weak diprotic acid

HOCH₂CH₂NH₂ => since there is an amine group, the compound is basic. It is weakly basic since NH2- groups are weak bases.

K₂HPO₄ => it is a salt of potassium and since there is one ionisable H atom, it is weakly acidic

Hg₂(CN)₂ => it a slightly soluble salt.