Chapter 18, Problem 11STP

To determine

The number of electrons present in the outer energy level of a helium atom.

Answer to Problem 11STP

The correct option is (B).

Explanation of Solution

Given:

The atom is helium.

Calculation:

Hydrogen and helium are 2 elements that can have a maximum of 2 outermost electrons. Rest all the elements can have a maximum of 8 electrons in the valence shell.

The number of electrons in the outer energy level of the helium atom is not either 1 or 3 or 4. Rather total number of electrons in outer energy level is 2.

Thus, the options (A), (C) and (D) are wrong, and option (B) is correct.

Conclusion:

Hence, the 2 electrons are present in the outer energy level of the helium atom.