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In this video, we want to turn these chemical names into chemical formulas for ionic compounds.
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They involve polyatomic ions.
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And so for those, you kind of just have to know the formula or you can look it up in the charge.
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And then everything else is elements, which you can reference from the periodic table.
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If you have an ionic compound, you're going to have a metal and a non -metal.
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The metal is going to have some positive charge and the non -meddle is going to have some negative charge.
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And you want the overall amount of positive and negative charge to balance out to zero.
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So let's keep all of that in mind.
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All right.
00:37
So for part a, ammonium is a polyatomic ion, which is nh4 plus.
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And acetate is also, it's c2, h3, o2, and a minus one charge.
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When they have the same charge, you need one of each to balance it out.
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So we'll just write nh4 for ammonium and then c2h3o2.
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That's our formula.
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All right.
00:58
Ferris.
01:00
So when you have ferris versus ick, the ending, that's an old -fashioned way to say it.
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But this is basically just saying that it's iron three, iron in the, iron two, sorry, iron in the lower oxidation state.
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So that's going to be fe with a two plus charge.
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And then hydroxide is oh minus.
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So if we have a plus two and a minus one, we need twice as much of the negative to balance it out.
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So we'll say fe and then oh should have a subscript of two.
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But the whole thing has a subscript.
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So when you have a polyatomic ion, you need to put parentheses to show that the subscript applies overall.
01:35
All right, part c.
01:36
So we have cobalt three.
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Roman numeral indicates the charge, so 3 plus, and then carbonate is co3, 2 minus.
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All right.
01:43
So if we have three and a two, the smallest whole number coefficient we could do to make the charge the same as six, least common multiple...