00:02
Hi there.
00:03
This question wants to know the symbol for two different ions.
00:07
So when we're writing a symbol, we write the elements one or two letter symbol.
00:13
And then the atomic number is written as a subscript before the symbol.
00:19
The mass number is written as a superscript before the symbol.
00:25
And the charge is written as a superscript after the symbol.
00:30
All right.
00:31
So let's talk about each of these for a moment.
00:32
Atomic number is defined as the number of protons in the atom.
00:42
So the number of protons identifies the atom and is the atomic number.
00:47
The mass number is going to be the sum of the protons plus the neutrons.
00:59
All right, and then the charge, a way we can calculate the charge is by taking the number of protons and subtracting the number of electrons.
01:24
Since protons are positively charged, electrons are negatively charged, if we subtract the number of electrons, we will get the charge...