Name a solid which can be used instead of concentrated sulphuric acid to prepare ethylene by the dehydration of ethanol.

Explanation

To answer the question, we need to identify a solid that can be used in place of concentrated sulfuric acid for the dehydration of ethanol to produce ethylene.

### Step-by-Step Solution:

1. **Understand the Reaction**: The dehydration of ethanol (C2H5OH) involves the removal of a water molecule (H2O) to form ethylene (C2H4). This reaction typically requires a dehydrating agent.

2. **Identify Common Dehydrating Agents**: Concentrated sulfuric acid (H2SO4) is a common dehydrating agent used for this purpose. However, we are looking for a solid alternative.

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