Question #fab79

1 Answer
May 12, 2017

The atomic number of an element= number of protons

Explanation:

Revision Science

If you have an element #""_2^4 He#
where 2= atomic number
4= mass number

Adding a proton changes the atomic number, the mass number, basically the entire element.

#""_3^7 Li#
where 3= atomic number
7= mass number

Or if you lower the atomic number (proton number) by 1
#""_1^1 H#
1= atomic number
1= mass number

Hope this helps!