Salts - Acidic, Basic, or Neutral?

LiClO4

Neutral Li+, first column in periodic table, therefore neutral ClO4-, conjugate acid is the strong acid HClO4

NaNO₃

Neutral Na+, first column in periodic table, therefore neutral NO3-, conjugate acid is a strong acid, therefore it is neutral

C6H5NH3NO2 C6H5NH3+ Ka = 2.50 x 10-5 NO2- Kb = 2.50 x 10-11

Acidic C6H5NH3+, conjugate base is a weak base, therefore it is potentially acidic NO2-, conjugate acid is a weak acid, therefore the salt is also potentially basic However, since the Ka > Kb, the solution must be acidic

NH4Br

Acidic NH4+, conjugate base is a weak base, therefore it is acidic Br-, conjugate acid is a strong acid, therefore it is neutral

K2CO3

Basic K+ comes from the first column in the periodic table, so it is neutral. CO3^2- has the conjugate acid HCO3^-, which is a weak acid, therefore it is a weak base.

KCN

Basic K+, first column in periodic table, therefore neutral CN-, conjugate acid is the weak acid HCN, therefore it is basic

RbF

Basic Rb+, first column in periodic table, therefore neutral F-, conjugate acid is the weak acid HF, therefore it is basic