Question

hydrogen has three isotopes ^1h, ^2h, and ^3h. what is the difference between these three isotopes?
the number of protons ranges from 1 to 3.
the number of electrons ranges from 1 to 3.
the number of neutrons ranges from 0 to 2.
the number of neutrons ranges from 0 to 2.
the number of protons ranges from 0 to 2.

Explanation:

Step1: Recall isotope definition

Isotopes of an element have same number of protons but different number of neutrons.

Step2: Analyze hydrogen isotopes

Hydrogen ($^1$H, $^2$H, $^3$H) always has 1 proton.
$^1$H has 0 neutrons, $^2$H has 1 neutron, $^3$H has 2 neutrons. So the number of neutrons ranges from 0 - 2.

Answer:

The number of neutrons ranges from 0 to 2.