how many electrons are in the third energy level?

Step 1: Define the Problem

Determine the number of electrons that can occupy the third energy level of an atom.

Step 2: Break Down the Problem

1. Identify the formula for the maximum number of electrons in an energy level.
2. Apply the formula to the third energy level.

Step 3: Apply Relevant Concepts

The maximum number of electrons in an energy level is given by the formula $2n^2$, where $n$ is the principal quantum number (energy level).

Step 4: Analysis, Verify and Summarize

• For the third energy level, $n = 3$.
• Calculate the maximum number of electrons: $2n^2 = 2 \times 3^2 = 2 \times 9 = 18$

Final Answer

The third energy level can hold a maximum of 18 electrons.