In `s`- and `p`-block elements the `OS`. changes in 2 units, but in transition elements it changes it chnages in units of one.(T/F)

Explanation

To determine whether the statement is true or false, we need to analyze the oxidation states (OS) of the s- and p-block elements compared to the transition elements (d-block).

### Step-by-Step Solution:

1. **Understanding Oxidation States in s- and p-block Elements**:
- In s-block elements (Group 1 and Group 2), the oxidation states typically vary by 1 or 2 units. For example, alkali metals (Group 1) have an oxidation state of +1, while alkaline earth metals (Group 2) can have oxidation states of +2.
- In p-block elements, the oxidation states can change by 2 units due to the presence of the inert pair effect. For instance, elements like lead (Pb) can exhibit oxidation states of +2 and +4.

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