Lisa, give Ms. Williams time to explain first before you ask questions
Good morning class, today we will be learning about Ionic compounds.
It's okay Mia, Lisa is just confused. An Ionic compound is a compound made up of ions. Ions are atoms that gain or lose electrons, and by them gaining or losing electrons determines if they have a positive or negative charge.
Wait, Ms. Williams. Ions can have a positive or negative charge?
Yes, the elements in the periodic table have charges by groups. For example in group 1 the charge is +1, so every element in group 1 has a charge of + 1, which means the elements lose one electron.
Why do they lose 1 electron if the charge is +1?
Back to what I was saying. An Ionic compound is a combination of ions. For example, Sodium and Chlorine combined and created this formula (NaCl) since Na has a charge of +1 and Cl has a charge of _1 they cancel out.
They lose 1 electron because the elements want to be stable, so they try to be like the element next to them.
Well what if they don't have the same number and cancel out?
What do you do in this rule?
Good question! If they don't cancel out it's a rule you have to use it's called the criss cross rule.
To find the formula of an Ionic compound that charges don't cancel out, you have to switch the charges.
Oh,Okay I think I'm starting to get it
Let me give you and example. Sodium oxide is Na2 O. Na has a charge of+1 and O has a charge _2 so you switch the charges and the formula will be Na2 O.