Question

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

Answer 1

To accurately assess the relationship between nitrogen and oxygen based on their electron configurations in the periodic table, let's explore each statement:

- **A. they have the same number of valence electrons**: This is false. Nitrogen has 5 valence electrons (configuration: 1s² 2s² 2p³), while oxygen has 6 valence electrons (configuration: 1s² 2s² 2p⁴).

- **B. they have the same number of electrons**: This is also false. Nitrogen has 7 electrons, while oxygen has 8 electrons.

- **C. they have valence electrons in different levels**: This is false. Both nitrogen and oxygen have valence electrons in the same energy level, which is the second level (n=2).

- **D. they have valence electrons in the same energy level**: This is true. Both elements have their valence electrons in the second energy level.

Thus, the correct statement is **D. they have valence electrons in the same energy level**.