Predict whether the following solutions are acidic, basic, or nearly neutral:

a. NaBr, b. K2SO3, c. NH4NO2, d. Cr (NO3). the answer is neutral, basic, acidic, acidic and i am not sure why

If you have alkali and a weak acid then the solution is basic.

For example K2SO3. The base is KOH it is soluble (alkali) and the acid is H2SO3 which is weak. So you have basic solution.

If you have a strong acid and an insoluble (weak) hydroxide then the solution is acidic.

Cr (NO3) 2. Cr (OH) 2⬇ is a weak hydroxide and HNO3 is a strong acid. The solution is acidic.

If you have a weak base and a weak acid you will have neutral solution. Also, you will have neutral solution if a strong base and a strong acid react.

I'm really sorry for my English.

And I think c is neutral not acidic. Because NH4OH is a very weak base and HNO2 is a very weak acid.