The salt formed when strong acid reacts with strong base is

Step 1: Analyze the question We are asked what type of salt forms when a strong acid reacts with a strong base (e.g., HCl + NaOH).

Step 2: Explain the concept Salts are classified by how completely the acid's replaceable hydrogen ions (H⁺) and the base's hydroxide ions (OH⁻) are neutralised:

• Normal salt: all replaceable H⁺ of the acid have been replaced by a metal or ammonium ion. Examples: NaCl, Na₂SO₄, KNO₃.
• Acid salt: only some replaceable H⁺ are replaced (e.g., NaHSO₄).
• Basic salt: the base is only partly neutralised and still contains OH⁻ (e.g., Zn(OH)Cl).
• Double salt: two different salts crystallise together (e.g., alum, K₂SO₄·Al₂(SO₄)₃·24H₂O).
• Complex salt: contains a complex ion (e.g., K₄[Fe(CN)₆]).

Step 3: Solve Take the example:

HCl + NaOH → NaCl + H₂O

• The acid is fully neutralised by the base.
• No H⁺ is left over in the salt, and no OH⁻ is left over either.
• The resulting solution is neutral (pH ≈ 7), because neither Na⁺ nor Cl⁻ hydrolyses in water.

A complete neutralisation like this gives a normal salt.

Another example: H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O. Here the acid is fully neutralised, so Na₂SO₄ is a normal salt.

Step 4: Answer The salt formed is a normal salt, which is option A.

Exam tip: Remember "Strong + Strong = Normal and Neutral". When the acid and base are in the correct proportions, the product is a normal salt with pH 7. For "basic" salts, look for a leftover OH⁻ in the formula, and for "acid" salts, look for a leftover H.