00:01
For this question, you're asked to calculate the mass of a particular reactant or product, given the mass of another reactant or product.
00:08
First, you need to write the balanced chemical reaction.
00:11
Solid, lead, two sulfide reacts with oxygen.
00:15
In the process, it says it produces solid lead to oxide and sulfur dioxide.
00:22
So, lead to sulfide, lead with a 2 plus charge, sulfide with a 1 minus charge, gives us one of each of them, reacting with oxygen gas, oxygen, is diatomic, so it's o2, produces lead two oxide.
00:37
Lead 2 has a 2 plus charge, oxygen, oxide has a 2 minus charge, so we have just one of each of them, and sulfur dioxide, meaning one sulfur and dye meaning two, two oxygens.
00:52
To balance this, if we put a three halves here, we have one lead, one lead, one sulfur, one, two, three oxygens.
01:03
So how do we get three out of two? we multiply it by three halves.
01:06
Now we have three oxygens, but we can't leave it like that, so we need to multiply everything through by two in order to get our balanced chemical reaction.
01:15
Next, it asks you to calculate how many grams of oxygen are required to react with 29 .9 grams lead two sulfide.
01:24
So we'll start with our 29 .9 grams lead two sulfide.
01:28
Convert the lead two sulfide into moles lead two sulfide by dividing by the molar mass lead two sulfide 239 .3 grams per mole.
01:38
Then when we have moles lead to sulfide, we can convert the moles lead to sulfide into moles of oxygen, seeing the two to three relationship.
01:48
Then when we have moles oxygen, we simply multiply by the molar mass of oxygen to get grams of oxygen.
01:57
6 .00 grams of oxygen are required to react with 29 .9 grams led to sulfide...