Chemistry
Grade-7
Easy

Question

The non-metallic element that is purple black color is

  1. Iodine
  2. Chlorine
  3. Graphite
  4. Aluminum

hintHint:

It is present in common salt.

The correct answer is: Iodine


    The correct option is Iodine.
    • The Greek word for iodine is lilac or purple, and this color is due to the color of the element iodine vapor.
    • Iodine is a bluish-black solid (at room temperature) that sublimates into a purplish-pink gas. And we know that this color of iodine is due to the absorption of visible light by electronic transitions between the highest and lowest molecular orbitals.
    • Put another way, we can say that the purple color of iodine is due to electronic transitions of lone pairs to sigma antibonding orbitals under visible light.
    • In this transition, iodine absorbs red light from the visible range and emits violet.

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    Which is the 5th rare gas present in the atmosphere?

    The correct option is d)Xe.

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    • Neon is simply written Ne.

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