Answer :

To determine which value is most likely to be the pH of a salt solution formed by the reaction of a base, we need to understand the nature of pH values and how they relate to the properties of acids and bases.

1. pH Scale Understanding:
- The pH scale ranges from 0 to 14 and measures how acidic or basic a solution is.
- A pH of 7 is considered neutral. Pure water has a neutral pH of 7.
- Values less than 7 indicate an acidic solution.
- Values greater than 7 indicate a basic (alkaline) solution.

2. Properties of Bases:
- Bases are substances that accept hydrogen ions (H⁺) and typically have a pH greater than 7.
- Common examples of bases include sodium hydroxide (NaOH) and potassium hydroxide (KOH).

3. Salt Solution from Base Reaction:
- When a base reacts with an acid, it forms a salt and water. The resulting solution will have certain pH characteristics depending on the strength of the base and the acid involved in the reaction.
- Since we are considering the reaction involving a base, we expect the resulting salt solution to be on the basic side of the pH scale, meaning the pH should be greater than 7.

Given the options provided:
- 2.0
- 7.0
- 8.0
- 10.0

Analyzing each:
- 2.0: This is a strongly acidic pH, which is not characteristic of a solution formed from a base.
- 7.0: This is neutral and unlikely to be the result in the context of reacting a base to form a salt solution.
- 8.0: This is slightly basic, which could be a result for a weak base, but not highly characteristic for a solution formed by a strong base.
- 10.0: This is a clearly basic pH, consistent with the typical pH values of solutions resulting from reactions involving bases.

The most likely pH value of a salt solution formed by the reaction of a base is:
10.0