Two representative elements, nitrogen and oxygen are in the same period of the periodic table. Which statement correctly describes the atoms of the two elements?

Question

A. They have valence electrons in the same energy level.
B. They have the same number of valence electrons.
C. They have valence electrons in different energy levels.
D. They have the same number of electrons.

Answer 1

The correct statement that describes the atoms of nitrogen and oxygen is:

A. They have valence electrons in the same energy level.

Both nitrogen and oxygen are in period 2 of the periodic table, which means their valence electrons are in the second energy level (n=2).

To clarify the other options:

• B is incorrect because nitrogen has 5 valence electrons (group 15), whereas oxygen has 6 valence electrons (group 16).
• C is incorrect because they do not have valence electrons in different energy levels; they are both in the same energy level (n=2).
• D is incorrect because nitrogen has 7 electrons, while oxygen has 8 electrons.

So, the best choice is A.