Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of the reaction involved?
(i) Displacement reaction
(ii) Precipitation reaction
(iii) Combination reaction
(iv) Double displacement reaction

Options

A. Only(i)
B. Only (ii)
C. Only (iv)
D. `(ii) and (iv)`

Explanation

To determine the type of reaction that occurs when barium chloride reacts with ammonium sulfate to form barium sulfate and ammonium chloride, we can follow these steps:

### Step 1: Write the Chemical Equation
The first step is to write the balanced chemical equation for the reaction.

**Reactants:**
- Barium Chloride: \( \text{BaCl}_2 \)
- Ammonium Sulfate: \( \text{(NH}_4)_2\text{SO}_4 \)

**Products:**
- Barium Sulfate: \( \text{BaSO}_4 \) (which is a white precipitate)
- Ammonium Chloride: \( \text{NH}_4\text{Cl} \)

**Balanced Equation:**
\[ \text{BaCl}_2 + \text{(NH}_4)_2\text{SO}_4 \rightarrow \text{BaSO}_4 + 2\text{NH}_4\text{Cl} \]

### Step 2: Identify the Type of Reaction
Next, we need to identify the type of reaction.

- **Displacement Reaction:** This involves one element being displaced by another in a compound.
- **Combination Reaction:** This involves two or more substances combining to form a single product.
- **Precipitation Reaction:** This involves the formation of an insoluble solid (precipitate) from a solution.
- **Double Displacement Reaction:** This involves the exchange of ions between two compounds.

In our reaction, we see that barium ions (\( \text{Ba}^{2+} \)) and ammonium ions (\( \text{NH}_4^{+} \)) exchange places with sulfate ions (\( \text{SO}_4^{2-} \)) and chloride ions (\( \text{Cl}^{-} \)). This indicates that it is a double displacement reaction.

### Step 3: Conclusion
Since a precipitate (barium sulfate) is formed and there is an exchange of ions, the correct classification of the reaction is:
- **Double Displacement Reaction**
- It can also be classified as a **Precipitation Reaction** due to the formation of a precipitate.

Thus, the correct options are:
- (ii) Precipitation reaction
- (iv) Double displacement reaction

### Final Answer:
The reaction is classified as both a double displacement reaction and a precipitation reaction.

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