An element X which is a yellow solid at room temperature shows catenation and allotropy. X forms two oxides which are also formed during the thermal decomposition of ferrous sulphate crystals and are the major air pollutants.
Locate the position of the element in the Modern Periodic Table

Explanation

To solve the question, we need to identify the element X based on the given properties and then locate its position in the Modern Periodic Table.

### Step-by-Step Solution:

1. **Identify the Properties of Element X**:
- Element X is described as a yellow solid at room temperature.
- It exhibits catenation and allotropy.
- It forms two oxides that are also produced during the thermal decomposition of ferrous sulfate crystals.
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