Beryllium has an atomic number of 4. How many neutrons does the isotope beryllium-9 have?(1 point)

Question

Responses

9
9

4
4

5
5

13

Answer 1

The isotope beryllium-9 has an atomic number of 4, which means it has 4 protons. The number after the hyphen (9) represents the total number of protons and neutrons in the nucleus of the atom.

To find the number of neutrons, you can use the following formula:

\[ \text{Number of neutrons} = \text{Mass number} - \text{Number of protons} \]

For beryllium-9:

\[ \text{Number of neutrons} = 9 - 4 = 5 \]

So, beryllium-9 has 5 neutrons.

The correct response is:

5