The salt formed by complete neutralisation of calcium hydroxide with ic acid of sulphur having four oxygen atoms is.

Options

A. calcium sulphite
B. calcium bisulphate
C. calcium sulphate
D. calcium bisulphite

Explanation

To solve the question regarding the salt formed by the complete neutralization of calcium hydroxide with sulfuric acid, follow these steps:

### Step-by-Step Solution:

**Step 1: Identify the Reactants**
- The reactants in this reaction are calcium hydroxide and sulfuric acid.
- Calcium hydroxide is represented as \( \text{Ca(OH)}_2 \).
- Sulfuric acid, which has four oxygen atoms, is represented as \( \text{H}_2\text{SO}_4 \).

**Step 2: Write the Neutralization Reaction**
- The general reaction for the neutralization of an acid by a base can be written as:
\[ \text{Base} + \text{Acid} \rightarrow \text{Salt} + \text{Water} \]
- For our specific case, the reaction will be:
\[ \text{Ca(OH)}_2 + \text{H}_2\text{SO}_4 \rightarrow \text{Salt} + \text{Water} \]

**Step 3: Determine the Products**
- When calcium hydroxide reacts with sulfuric acid, the products formed are calcium sulfate (the salt) and water.
- The balanced chemical equation for this reaction is:
\[ \text{Ca(OH)}_2 + \text{H}_2\text{SO}_4 \rightarrow \text{CaSO}_4 + 2\text{H}_2\text{O} \]

**Step 4: Identify the Salt**
- The salt formed in this reaction is calcium sulfate, which is represented as \( \text{CaSO}_4 \).

### Final Answer:
The salt formed by the complete neutralization of calcium hydroxide with sulfuric acid is **calcium sulfate (CaSO₄)**.

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