Use the equation to answer the question.

Question

21H+ 21H→ 42H+energy

Which statement best describes the mass numbers of the atoms in the reaction?

(1 point)
Responses

There are two atoms with mass numbers of 1.
There are two atoms with mass numbers of 1.

There is one atom with a mass number of 1.
There is one atom with a mass number of 1.

There is one atom with a mass number of 2.
There is one atom with a mass number of 2.

There are two atoms with mass numbers of 2.
There are two atoms with mass numbers of 2.

Answer 1

In the equation provided, \(^{21}H + ^{21}H \rightarrow ^{42}H + \text{energy}\), the notation \(^{21}H\) indicates that each hydrogen atom has a mass number of 2 (the superscript indicates the mass number). Thus, we can analyze the mass numbers as follows:

• Each of the reactants \(^{21}H\) has a mass number of 2.
• The product \(^{42}H\) also has a mass number of 2.

Therefore, the correct statement that best describes the mass numbers of the atoms in the reaction is:

There are two atoms with mass numbers of 2.