00:03
Hi there.
00:03
In this question, we have a reaction described, and the first thing we want to do is to write the balanced equation for this reaction.
00:12
So we are starting with tetrophosphorus decoxide.
00:16
And they give us the formula for it as p4 -o -10.
00:21
This is reacting with water.
00:24
H -2 -o is the formula for water.
00:28
And we are producing, so we need an arrow, phosphoric acid.
00:32
Well, phosphoric acid is the phosphate ion with three hydrogen.
00:37
So h3, p .o4 is phosphoric acid.
00:43
All right.
00:44
So to balance this, when we're balancing means we add coefficients that we end up with the same number of each type of atom on both sides of the arrow.
00:51
We have four phosphorus on the reactant side and only one on the product side.
00:55
So i'm going to put a four in front of h3po4.
01:03
Next, let's look at the oxygen.
01:05
Actually, let's look at the hydrogen next because oxygen is in both of our reactants.
01:09
So let's balance the hydrogen next and then work with our oxygen.
01:14
On the product side, we have four times three or 12 hydrogen.
01:17
On the reactant side, there's only two.
01:19
So we need a six in front of h2o.
01:22
Now if we look at the oxygen, we have 10 in p4010 plus six more in the water molecules for 16 on the reactant side.
01:30
On the product side, we have four as the coefficient times the subscript of four, which is 16.
01:37
All right, so this equation is balanced.
01:40
So we have our balanced chemical equation.
01:43
And the next thing we want to know is the number of moles for each reactant that are required to give us 5 .80 moles of the acid.
01:59
All right.
02:00
Well, this is a mole ratio problem.
02:02
That is why we needed the balanced equation, because the balanced equation gives us the mole ratio.
02:07
The mole ratio comes from the coefficients in that balanced equation...