Answer:
CH₃COOLi → Basic
C₂H₅NHCl → Acid
KF → Basic
KNO₃ → Neutral
KClO₄ → Basic
Explanation:
We dissociate the salts, we define if they are conjugate weak or strong acid and base, and we determine if they can react to water. So that's the way to find out when the salt, gives protons to the medium (acidic salt) or hydroxides (basic salt)
CH₃COOLi → Lithium acetate
This salt comes from a strong base LiOH and a weak acid, the acetic.
This is the salt's dissociation: CH₃COOLi → CH₃COO⁻ + Li⁺
Lithium cation corresponds to the conjugate weak acid, of the strong base. It won't react in water. While the acetate can react to water to give acetic acid. This is the equillibrium:
CH₃COO⁻ + H₂O ⇄ CH₃COOH + OH⁻ Kb
Salt can release hydroxides, so it is a basic salt.
C₂H₅NHCl → Aziridinium chloride
C₂H₅NHCl → C₂H₅NH⁺ + Cl⁻
When this salts dissociates we have aziridinium and chloride. The chloride is the conjugate weak base, from the strong acid, hydrochloric acid. The aziridinium (strong conjugate acid) comes from the weak base, aziridine so it will react to water to produce again, the aziridine.
C₂H₅NH⁺ + H₂O ⇄ H₃O⁺ + C₂H₅N Ka
We are giving protons to the medium, so this salt is acid.
KF → Potassium fluoride
This salts dissociates in potassium cation and fluoride anion
KF → K⁺ + F⁻
K⁺ comes from the strong base KOH. The cation is the weak conjugate acid so it won't react in water while the fluoride as it comes form the hydrofluoric acid (a weak one), the anion is the conjugate strong base. This ion can react to water according to:
F⁻ + H₂O ⇄ HF + OH⁻ Kb
This salt will be basic, cause we are giving OH⁻.
KNO₃ → Potassium nitrate
KNO₃ → K⁺ + NO₃⁻
Both ions come from a strong base(KOH) and a strong acid (HNO₃), respectively. They are the conjugate weak acid (K⁺) and the weak conjugate base (NO₃⁻) of them. They won't react to water, so no protons or hydroxides are given in this case. The salt will be neutral.
KClO₄ → Potassium chlorate
KClO₄ → K⁺ + ClO₄⁻
As we said, potassium cation corresponds to the KOH. It is the conjugate weak acid of the strong base and it won't react to water. In the case of the chlorate, it comes from the chloric acid which is weak. So this anion is the conjugate strong base. It react to water to produce, the acid again according to these equilibrium:
ClO₄⁻ + H₂O ⇄ HClO₄ + OH⁻ Kb
This salt will be basic.
