Question

In which of the following systems will the radius of the first orbit (n = 1) be minimum?

• A. Doubly ionized lithium
• B. Singly ionized helium
• C. Deuterium atom
• D. Hydrogen atom

Answer 1

Answer: (A)

Doubly ionized lithium

Answer 2

Radius of first orbit, $r \propto \frac{1}{Z},$

For doubly ionized lithium Z (=3) will be maximum hence for doubly ionized lithium r will be minimum