# How many electrons, protons, and neutrons does nitrogen-14 have? Is it an anion or cation?

## I know nitrogen-14 has 7 protons, but I do not know how many neutrons or electrons. Cations are positively charged ions while anions are negatively charged.

Oct 17, 2017

$7$ electrons, $7$ protons, and $7$ neutrons.

#### Explanation:

Nitrogen-14 is actually an isotope of nitrogen, so right from the start, you can say that it is a neutral atom.

Isotopes are atoms that have the same number of protons but different numbers of neutrons in the nucleus. You know that nitrogen-14 has $7$ protons in the nucleus because it is an isotope of nitrogen, which has an atomic number equal to $7$.

Because nitrogen-14 is a neutral atom, the number of protons it has in its nucleus must be equal to the number of electrons that surround its nucleus.

$\text{neutral atom " implies " no. of protons = no. of electrons}$

Now, in order to find the number of neutrons present in the nucleus of a nitrogen-14 atom, you must use its mass number. The mass number of an isotope is added to the name of the isotope.

In this case, you have

$\text{nitrogen-"color(blue)(14) implies "mass number} = \textcolor{b l u e}{14}$

The mass number of an atom tells you the number of protons and neutrons located in the nucleus.

So you can say that

$\text{no. of protons + no. of neutrons} = \textcolor{b l u e}{14}$

This implies that a nitrogen-14 atom contains

(color(blue)(14)color(white)(.)"protons + neutrons") - "7 protons" = "7 neutrons"

Now, a nitrogen atom, regardless of its mass number, will always form $3 -$ anions, ${\text{N}}^{3 -}$. In other words, any nitrogen atom will take in $3$ electrons to complete its octet--this happens because nitrogen is located in group $15$ of the Periodic Table.