Question

Given that oxygen-16 and oxygen-18 both have an atomic number of 8, how many electrons, protons, and neutrons do these oxygen atoms contain?
Question 7 options:

Any oxygen atom contains 8 electrons and 9 neutrons but these vary in the number of protons - 8 and 10 respectively.


These oxygen configurations contain the same number of subatomic particles - 8 electrons, 6 protons and 10 neutrons.


The oxygen isotopes contain 8 electrons but each contains a different number of neutrons and protons - 8 and 10 respectively.


Both oxygen isotopes contain 8 electrons and 8 protons but each contains a different number of neutrons - 8 and 10 respectively.

Answer 1

Because atomic number equals protons and electrons
8-electrons
8-protons
Protons+neutrons=mass
8+8=16 and 8+10=18
8-Neutrons for 16
10- Neutrons for 18

Answer 2

Answer: The correct answer is both oxygen isotopes contain 8 electrons and 8 protons but each contains a different number of neutrons - 8 and 10 respectively.

Explanation:

Atomic number is defined as the number of protons or electrons that are present in a neutral atom.

Atomic number = number of protons = number of electrons

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

For the given representation of ion, which is:  $^{8}_{16}\textrm{O}\text{ and }^{8}_{18}\textrm{O}$

• For first isotope:

Number of protons = Number of electrons = Atomic number = 8

Mass number = 16

Number of neutrons = 16 - 8 = 8

Thus, this isotope has 8 protons, 8 electrons and 8 neutrons.

• For second isotope:

Number of protons = Number of electrons = Atomic number = 8

Mass number = 18

Number of neutrons = 18 - 8 = 10

Thus, this isotope has 8 protons, 8 electrons and 10 neutrons.

Hence, the correct answer is both oxygen isotopes contain 8 electrons and 8 protons but each contains a different number of neutrons - 8 and 10 respectively.