What is the effect of temperature on the conductivity of metals and semi-metals ?

Explanation

### Step-by-Step Solution:

1. **Understanding Conductivity**:
- Conductivity is the ability of a material to conduct electric current. It depends on the availability of charge carriers (like electrons) and their mobility.

2. **Effect of Temperature on Metals**:
- In metals, as the temperature increases, the kinetic energy of the metal atoms also increases.
- This increase in kinetic energy causes more frequent collisions between the conduction electrons and the vibrating metal ions.
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