Use the equation to answer the question. 21H+ 21H→ 42H+energy Which statement best describes the mass numbers of the atoms in the reaction? (1 point) Responses 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 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 are two atoms with mass numbers of 2. There are two atoms with mass numbers of 2.

Answer 1

In the equation \(21H + 21H → 42H + \text{energy}\), we can analyze the mass numbers of the atoms involved:

• The left side of the equation has two hydrogen atoms, each with a mass number of 1 (noted as \(21H\)).
• On the right side, the product is one atom with a mass number of 2 (noted as \(42H\)).

Thus, the statements about the mass numbers can be summarized as follows:

• There are two atoms with mass numbers of 1 (the two \(21H\) atoms on the left).
• There is one atom with a mass number of 2 (the \(42H\) atom on the right).

Based on the options provided, the best statement that describes the mass numbers of the atoms in the reaction is:

There are two atoms with mass numbers of 1.