Achieve HW #7

[Ivy Nguyen 3I]

Can someone walk me through their thought process for #7? I got the answer after multiple attempts but still don't fully understand how to do it. Also, attached is part of the explanation, can someone explain the part where it states "pull H+ from water and be basic" and vice versa for acidic? Thank you!

[Ashley M 2E]

How I worked this question out was I would determine what each ion would be if it was dissolved in solution. If both ions in a salt are typically part of a strong acid or strong base, it would be neutral. For instance, KCl would have K+ ions and Cl- ions, K+ being the cation of a strong base and Cl being the anion of a strong acid, so it would be neutral. For K3PO4 or NaCN, though, only the cation is typically from a strong base. PO4 and CN are anions that are derived from weak acids (they are the conjugate base to the acids). Because they are technically conjugate bases, they want to accept H+ and act basic in solution, which is what the solution means when it says that it pulls H+ to be basic. The opposite occurs for NH4ClO4, where NH4+ is a conjugate acid of NH3.