Question

1. which of these describes two isotopes of hydrogen? select all that apply.

they have similar chemical properties.
they have the same mass number.
they have different numbers of neutrons.
they are different elements.

Explanation:

• Isotopes of an element have the same number of protons (so they are the same element) and similar chemical properties (since chemical properties are mainly determined by the number of electrons, which is related to the number of protons).
• They have different numbers of neutrons (which causes different mass numbers as mass number = number of protons + number of neutrons).

Answer:

• They have similar chemical properties.
• They have different numbers of neutrons.