Question

Nitrogen (N) has an atomic number of 7 and an atomic mass of 14. Which of the following correctly shows the electron arrangement for nitrogen?

A. 2, 7

B. 2, 5

C. 2, 2, 3

D. 2, 8, 4

Answer 1

7 protons means that Nitrogen atom has 7 electrons.

the 1st shell can have only 2 electrons, and we have left over of 7-2=5 e⁻, that will go on the second shell.

thus the answer, B. 2,5

Answer 2

7 protons means that N atom has 7 electrons
1st level can have only 2 e⁻, and we have left over of 7-2=5 e⁻, that will go on the second level.
B. 2,5