Coke, coal tar, coal gas and ammonia solution are produced when coal is subjected to __________ of coal.

Explanation

To solve the question, "Coke, coal tar, coal gas and ammonia solution are produced when coal is subjected to __________ of coal," we need to identify the process that leads to the formation of these products from coal.

### Step-by-Step Solution:

1. **Understanding the Products**: The question mentions four products: coke, coal tar, coal gas, and ammonia solution. These are all derived from coal.

2. **Identifying the Process**: The key to answering the question lies in knowing how these products are obtained from coal. The process that produces these substances is known as "destructive distillation."

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