00:02
Hi there.
00:03
In this question, we are working with a double displacement reaction, also known as a double replacement reaction.
00:10
It just depends upon your textbook, whether it calls it a double displacement or a double replacement.
00:17
But they're both the same thing.
00:20
In a double displacement reaction, we start with two aqueous ionic compounds, and they exchange ions.
00:29
So the positive ion from the first substance goes with the negative ion from the second, and the positive.
00:35
Ion from the second goes with the negative ion from the first.
00:39
In order for us to truly have a reaction here, we need to form an insoluble product.
00:44
So one of these new products needs to be insoluble.
00:48
Typically a precipitate, but it can also be a liquid or a gas.
00:53
All right, so we need the net ionic equation, but i like to write the what is called the molecular equation first, just to get that balanced, and then it makes it much easier to write the net ionic equation.
01:05
So i want to write the entire reaction of what's going on here.
01:09
We have potassium sulfide.
01:12
So potassium has a one plus charge and sulfide has a two negative.
01:17
So it needs to be k2s.
01:19
And this is reacting with iron two nitrate.
01:23
So the two refers to the charge on the iron.
01:26
Nitrate has a one negative charge.
01:29
So we would need two of those.
01:31
This is also aquas.
01:34
All right...