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Hi there.
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In this question, we are forming ionic compounds, and ionic compounds are formed from a cation, which is a positive ion, and an ion, which is a negative ion.
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The cation is formed from a metal that loses one or more electrons, and the anion is formed from a non -metal that gains one or more electrons.
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Remember, the whole purpose of losing or gaining electrons is to satisfy the octet rule.
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All right.
00:42
The other thing about ionic compounds is that they are neutral.
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In order to be neutral, the total positive and negative charges must add to zero.
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So we need to add subscripts as necessary so that the charges add up to zero.
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Okay, so let's go ahead and get started.
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In letter a, we have lithium.
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To determine how many electrons they're going to lose, or gain, we need to know how many valence electrons they have.
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So for the main group elements, the group number that they are in represents the number of valence electrons.
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So lithium is in group 1a.
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It's a metal.
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So it has one valence electron that it's going to lose.
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When it loses that, it'll have a positive charge.
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We're putting this with nitrogen, which is in group 5a.
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So it has five valence electrons.
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It needs to get to eight.
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The octet rule says, it wants 8, so it will gain three electrons.
01:53
And electrons are negatively charged, so it has a 3 negative charge.
01:57
All right, since the total positive and negative charges have to add to 0, we need to put a subscript of 3 here, making it li3n, because 3 times positive 1 is positive 3.
02:11
Adding that to negative 3 gives us li3m.
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So, rewriting it without the charges there.
02:19
It's just l .i .3n.
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And its name would be lithium.
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And it's with nitrogen.
02:28
But when we're naming ionic compounds, the anion's ending changes to ide...
