The mobile electrons in a metal occupy specified positions in the lattice and are not delocalised.

Explanation

To determine whether the statement "The mobile electrons in a metal occupy specified positions in the lattice and are not delocalized" is correct, we can analyze the properties of metals and their electron behavior. Here’s a step-by-step solution:

### Step 1: Understand the Structure of Metals
Metals have a crystalline structure where atoms are arranged in a regular, repeating pattern. This arrangement leads to a closely packed structure.

**Hint:** Recall that metals typically form a lattice structure due to their atomic arrangement.

### Step 2: Define Mobile Electrons
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