00:07
Okay, we're asked to use the law of conservation of mass.
00:11
We're told that the mass of reactants equals the mass of products.
00:19
We're asked to fill things out.
00:20
So a, we're given an unbalanced chemical equation, not balanced.
00:31
And i don't know if you've learned to balance yet or not.
00:34
And we're told that we have 3 .4 grams and we have 10 .0 grams.
00:42
And this would mean that i have 13 .4 grams if this is correct.
00:47
So let's see if this is correct.
00:51
3 .4 grams times 2 .02 grams per mole times 2 to 1 moles of o2 moles of h2 times 32 .00 grams.
01:17
And let me see what this equals just to see if i'm even in the ballpark here.
01:32
So if i had 3 .5 grams of hydrogen, that would give me one mole.
01:39
Oops, this is backwards.
01:45
3 .5 times 32 divided by 2 .02 divided by 2.
01:51
So this would give me 27.
01:53
I need 27.
01:54
So i don't actually have enough.
01:55
There's not enough.
02:01
O2 is limiting.
02:10
So i'm not exactly sure.
02:20
So as written, the highlighted portion is all you have to fill out.
02:42
Without stoichiometry, the answer is 13 .4.
02:54
With stoichiometry, the answer is, and let's do that, 10 .0 grams times 32 .00 grams per mole times 1 to 2 times 18 .02 would be 11 .3.
03:28
So there's your two options...