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### Course: High school chemistry>Unit 1

Lesson 2: Isotopes and ions

# Worked example: calculating ion charge

An atom with an electric charge is called an ion. The charge of an ion is equal to the number of protons minus the number of electrons. Created by Sal Khan.

## Want to join the conversation?

• How and why would an atom lose electrons?
• So basicly all atoms want is a full outer shell so they can gain stabitlity. They need to have a full outer shell of electrons so they can be stable. For example if a atom had a outer shell with 2 electrons it would rather lose those 2 electrons (causeing a chemical reaction) than gain 6. So it woudl lose these 2 electrons. And if your asking "hey that outer shell isnt full anymore its EMPTY" well, a shell with no electrons is basicly no shell so the shell before would become the outer shell. HOPE THIS HELPS (sorry for posting this answer in the comment earlier guys) ALSO RIP MY SPELLING
• why are there 2 blank spaces in the periodic table ?
• The 2 blank spaces mark the Lanthanides and Actinides, two series of elements that fit into those spaces. There are 14 elements in each of these groups. If they were included where the spaces are, the periodic table would be much wider (32 columns instead of 18 columns). Often, they are instead placed underneath the rest of the periodic table to compact it.

I hope that this helps! =)
• when fnding the charge of an ion does the number of neutrons matter
• Not at all. The charge of a neutron is `0`.
• What causes an atom to become an ion?
(1 vote)
• An atom has no charge, as it has the same number of protons (1+ charge) as electrons (1- charge). An ion has either more or less electrons than protons.
Atoms become ions by gaining or losing electrons.

I hope this helps! :-)
• So what do you call an atom that is both an ion and an isotope? Like Sal's last example of 7 protons, 8 neutrons, and 10 electrons.
(1 vote)
• Isotopes are just atoms of the same element, same proton number, but different number of neutrons. So all atoms are themselves isotopes since there are other atoms of the same element with different numbers of neutrons. There is no single ‘standard’ nonisotope version of an element.

Since it has a charge with excess of electrons, it would just be an ion.

Hope that helps.