The atomic mass of iodine is `127 g//mol`. A standing wave in iodine vapour at `400 k` has nodes that are `6:77 cm` apart when the frequency is `1000 H_(Z)`. At this temperature, is iodine vapour monatomic or diatomic.

Explanation

To determine whether iodine vapor is monatomic or diatomic at a temperature of 400 K, we can follow these steps:

### Step 1: Gather Given Information
- **Atomic mass of iodine (I)**: \( 127 \, \text{g/mol} \)
- **Temperature (T)**: \( 400 \, \text{K} \)
- **Frequency (f)**: \( 1000 \, \text{Hz} \)
- **Distance between nodes (L)**: \( 6.77 \, \text{cm} \)

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