Question

Which of the following radiations are not emitted by electron transitions in atoms ?

• A. Ultra-violet.
• B. Infra-red radiations.
• C. Visible rays.
• D. $\alpha$-rays.

Answer 1

Answer: (D)

$\alpha$-rays.

Electron transition within the atom releases electro magnetic radiation (chargeless).
Alpha rays have charge. Hence we can safely say that electron transitions within an atom wouldn't cause the release of alpha rays.

So, the answer is option (D).