Aluminium vessels should not be washed with materials containing washing soda because:

Options

A. washing soda is expensive
B. washing soda is easily decomposed
C. washing soda reacts with aluminium to form soluble aluminate
D. washing soda reacts with aluminium to form insoluble aluminium oxide

Explanation

To answer the question of why aluminum vessels should not be washed with materials containing washing soda, we can break down the reasoning step by step.

### Step-by-Step Solution:

1. **Understanding Washing Soda**:
- Washing soda is chemically known as sodium carbonate (Na2CO3). When dissolved in water, it dissociates to form sodium ions (Na+) and carbonate ions (CO3^2-).

**Hint**: Remember that washing soda is a basic compound that can affect the pH of the solution when dissolved in water.

2. **Reaction with Water**:
- When washing soda is mixed with water, it can produce sodium hydroxide (NaOH) through hydrolysis, which is a strong base. This reaction also releases carbon dioxide (CO2) gas.

**Hint**: Focus on the fact that washing soda can create a strong alkaline environment due to the formation of sodium hydroxide.

3. **Interaction with Aluminum**:
- Aluminum (Al) is a reactive metal. In the presence of sodium hydroxide, aluminum can react to form sodium aluminate (NaAl(OH)4). This reaction is significant because sodium aluminate is soluble in water.

**Hint**: Consider how aluminum reacts with strong bases and the products formed in such reactions.

4. **Corrosion of Aluminum**:
- The formation of sodium aluminate leads to the corrosion of aluminum vessels. Over time, this reaction can thin the aluminum, creating holes and weakening the structure of the vessel.

**Hint**: Think about the long-term effects of repeated exposure to strong bases on metals.

5. **Conclusion**:
- Therefore, the reason aluminum vessels should not be washed with washing soda is that it reacts with aluminum to form soluble sodium aluminate, which leads to the corrosion of the aluminum vessel.

**Hint**: Summarize the key point: the reaction produces a soluble compound that weakens the aluminum.

### Final Answer:
Aluminum vessels should not be washed with materials containing washing soda because washing soda reacts with aluminum to form soluble sodium aluminate, leading to the corrosion of the aluminum vessel.