Question

take a look 5. label the first energy level and second energy level in the oxygen atom of the water molecule. include in each label the number of electrons required to fill the level.

Explanation:

Step1: Recall electron - shell rules

The first energy level (n = 1) can hold a maximum of 2 electrons. It is called the K - shell.

Step2: Recall second - energy level rules

The second energy level (n = 2) can hold a maximum of 8 electrons. It is called the L - shell.

Step3: Apply to oxygen in water

Oxygen has an atomic number of 8. In a water molecule ($H_2O$), the oxygen atom has electrons distributed among energy levels. The first energy level of oxygen in water has 2 electrons (fully - filled), and the second energy level has 6 electrons (needs 2 more to be fully - filled).

Answer:

First energy level (K - shell): 2 electrons to fill. Second energy level (L - shell): 8 electrons to fill.