Identifying Acidic, Basic, Neutral Salts

[Carolina Gomez 2G]

In week 2, Sapling question 6, we have to identify salts as acidic, basic, or neutral. What are some ways to identify what they would be. Are there certain steps we have to follow or is it more based on being able to identify which come from a strong acid/ base or weak acid/ base?

[KatarinaReid_3H]

If it is a conjugate of a Strong Acid or Strong Base then it is neutral.
Ex: HCl -> H+(acidic) and then the Conjugate is Cl- which is neutral/salt
Ex: NaOH -> OH- (basic) and then the conjugate is Na+ which is neutral/salt

If it is a conjugate of a Weak Acid or Weak Base then it is slightly basic or acidic
Ex: HF -> H+ (acidic) and then F- is the conjugate base (it is very slightly basic)

[Victor Li 2A]

You basically break the salt apart into the cation and anion.

If the salt is made up of the conjugates of a strong acid and a strong base, then it is neutral.
If the salt is made up of the conjugate base of a strong acid and the conjugate acid of a weak base, then the salt is acidic.
If the salt is made up of the conjugate base of a weak acid and the conjugate acid of a strong base, then the salt is basic.

[Melody Wu 2L]

Victor's explanation is really great. If you want more explicit examples, check out table 6D.1 and 2 in the textbook! They show the different ions that contribute to making a salt solution acidic or basic.

Acidic solution:
- Conjugate acids of weak bases (ex. NH4+)
- Small, highly charged mental cations (ex. Al3+, Fe3+)

Neutral:
- Group 1 and 2 metal cations (ex. Li+, Na+, Ca2+)
- Conjugate bases of strong acids (ex. Cl-, Br-, I-, No3-)

Basic
- Conjugate bases of weak acids (ex. F-, OH-, CN-)

[Sahaj Patel Lec3DisK]

For Salts, you have to look at its composition. Salts will be made of a cation and anion. If the cation belongs to a strong base, and the anion is part of a weak base, it is a basic salt. If the cation belongs to a weak base, and the anion is part of a strong acid, it is a acidic salt. If both the cation and anion is part of a strong acid and base, then the salt is neutral.