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Current time:0:00Total duration:3:57

Video transcript

let's get some practice now thinking about how ions typically form how they might form compounds and how we need those compounds so let's start with something in Group one in this first column this first column is also known as alkali metals and so let's start with potassium K is the symbol for potassium now things in Group one here one way to think about is their outermost shell has one electron in it so they wouldn't mind losing that electron so when they ionize they tend to lose an electron and become a cation a positive ion and so let's look at a situation where I have some potassium that has been ionized and I could I could write it just like this we've seen that in previous videos and we can refer to this just as a potassium ion we could refer to this as potassium one plus we could refer this refer to this as a potassium cation now let's go on to the other side of the periodic table things that would really love to grab an electron so things in a group in the halides which is this column right over here so these are the halides they have seven electrons in their outermost shell they would love to have eight so they tend to be really good at grabbing electrons and so let's say we're dealing with chlorine and chlorine is able to ionize so it's able to grab an electron when chlorine grabs an electron it will be a negatively charged ion so you could write as chlorine one minus but the way that we generally refer to an anion a negatively charged ion instead of saying this is instead of just calling this the chlorine anion we would call this chloride so this we referred to as klore poor ID now as you can imagine with potassium having a positive one charge or one plus charge and this having a negative charge they're going to be attracted to each other and they can actually form an ionic compound and of the ionic compound they would form we would write as you'd write your positive ion first and then you would write your negative ion and this right over here would be described as potassium chloride let me write that down potassium potassium chloride now you might be saying well I just root let me rewrite though write the whole thing so you know the chloride part you say okay this is going to be an anion because instead of writing chlorine which is the name of this element I wrote this IDE at the end to say hey this is an anion so I know that this is this is the chlorine anion this is chloride why didn't I do something similar for potassium well the way the convention works is if someone says potassium chloride you know you're dealing with an ionic compound and if the chlorine has a negative one charge an ionic compound the whole thing is going to be neutral so this one over here is one minus then you know this over here since they're one for one this is going to be one plus so you know that you're dealing with a potassium cation and I you could say a core and a chloride ion or a chlorine anion you could refer to it other ways there are various ways but this is potassium chloride you have a positively charged potassium and you have a negatively charged chlorine which we would call a chloride in the next few videos we'll do many many more examples of this and once it'll be a lot a little bit more complicated