00:01
This problem has a few interesting parts.
00:03
So letter a asks us to find the empirical formula.
00:07
Letter b asks us to find the empirical formula, but we're given different things to start with, and then letter c is a balance chemical reaction.
00:13
So we're going to start with a and b, and then move on to c.
00:16
So a is pretty straightforward.
00:18
We're given the percents, so the first thing is converting them to grams by just changing the percent to gram.
00:24
The second thing then is converting those grams to mole.
00:26
So if we start with grams, grams have to go on the bottom, and one mole of that substance will go up top.
00:31
The molar mass of carbon is 12 .01.
00:35
So then we're going to go 60 .87 divided by 12 .01.
00:40
When we do that, we get 5 .068 moles of carbon.
00:45
We're going to do the same thing with hydrogen and oxygen.
00:48
So if we start with grams of hydrogen, grams of hydrogen must go on the bottom.
00:51
One mole of hydrogen is going to go at the top.
00:54
The molar mass of hydrogen is 1 .01.
00:56
So we're going to go 4 .38 divided by 1 .01.
01:00
When we do that, we get 4 .337.
01:07
Last but not least, we're going to do this with oxygen.
01:10
If we start with grams of oxygen, grams of oxygen have to go on the bottom.
01:13
One mole of oxygen is going to go to the top.
01:15
The molar mass of oxygen is 16.
01:19
So if we go 34 .75 divided by 16, we end up with 2 .172.
01:27
So then we're going to compare these three, and we're going to divide by the smallest -to -go ratio.
01:33
So the smallest is oxygen.
01:34
So we're going to divide all of them by 2 .172.
01:42
When we divide anything by itself, it's always 1 .4 .377 divided by 2 .172 gives us 2 .068.
01:55
Divided by 2 .172 is 2 .33.
02:03
So if all of these were whole numbers, we could just write those whole numbers.
02:06
So subscribes, call it a day.
02:07
However, since we have a decimal, we need to get rid of this decimal.
02:12
To do that, we're going to multiply it by three.
02:16
The reason is, is one -third equals 0 .33.
02:20
So to cancel that fraction, we're going to multiply it by three.
02:23
However, you can't just multiply one by three.
02:25
We have to multiply all of them by three.
02:28
So 2 .33 times three gives us seven.
02:33
Two times three is six, and one times three is three.
02:36
So the final formula for a would be, c7h603.
02:45
Letter b, we're given 4 .88 grams of product...