What is meant by a substance ?

Explanation

### Step-by-Step Text Solution:

1. **Understanding Matter**:
- Matter is anything that occupies space and has mass. Everything around us, such as objects, food, and even air, is considered matter.

2. **Defining Substance**:
- A substance is a specific type of matter that has a uniform and definite composition. It can be made up of one type of particle or more than one type of particle.

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