An element has 5 protons, 6 neutrons, and 5 electrons. What is the mass number?

1 Answer
Slangus
Nov 17, 2015

Mass number = protons + neutrons

Explanation:

The mass number of an element is the sum of the protons and neutrons. The number of neutrons for a given element is the only number that can change and still have the identity of the element stay the same, (because the atomic number is the number of protons).

In this case the mass number would be 11.

Related questions
See all questions in Mass Number
Impact of this question
56409 views around the world
You can reuse this answer
Creative Commons License