00:01
Problem 39 asks us to balance these chemical equations.
00:05
For the first one, we have two potassium on the left, so we need to make two potassium on the right.
00:12
So that balances our equation.
00:15
In the second equation, one iron in the left, one iron in the right, two hydrogens on the left, two hydrogen on the right, one oxygen on the left, one oxygen on the right.
00:26
This one is already balanced.
00:30
And then for this next one, we have one sodium on the left, one sodium on the right, one chlorine, on the left, one chlorine on the right, five oxygens on the left, five of oxygens on the right, two hydrogens on the left, two hydrogens on the right.
00:44
This one's already balanced as well.
00:48
This next one we have two manganese on the left, so balance, we need two over here.
00:54
We have three oxygens on the left, so we add three here.
00:59
And now we need to also add three on the left in front of magnesium to balance.
01:06
So for this one, i looked at the number of hydrogen, first and i could see that there are three on the left, two on the right.
01:15
So to make four on both sides, i added a two here and a two here.
01:24
And this also balances our potassiums with three on each side.
01:31
And our oxygens are also balanced.
01:34
So this equation is balanced.
01:39
So for this next one, the number of nitrogens are equal on both sides.
01:48
The number of hydrogens is two over here.
01:51
So put a two over here.
01:55
And then now you have two nitrogens on that side.
01:57
So you need to put two over here.
02:01
But now the number of oxygens, we have four, five, six, seven.
02:10
And we have six on this side...