A 69.5 g sample of the compound X 3 O 4 contains 19.2 g of oxygen atoms. What is the molar mass of element X?

Hey folks, welcome back. Alright, so here we need to identify the element X in X. V. R four. Given that it is 96.4% of blooming by mass. Right, so we have this unknown compound, We do know some information of grooming, we know that we have four bombings here and we also have the percentage of grooming. So what we can do is actually find the total mass of this compound of ex BR four Using the mass percent of blooming. So 96.4% of roaming by mass. That's going to equal to the mass of grooming. Right? The total mass of grooming divided by the total mass of that compound. So we actually don't have the total mass of grooming but we can figure it out because we know we have four of them in this formula. Right? So bro mean Four of them times it's smaller mass. If you take a look at the periodic table, you'll see that Mueller, massive roaming is about 79.9. So multiply that by four, that will be 319 0.6 g. Alright, so 3 19.6g is the total mass of roaming that we have here. So we can plug that in. So 3 19 .6 g of just blooming. Okay, now this we need to divide by the total mass. Come on, total mass of this compound of ex BR four And this is what we're going to solve for. We don't know that then times 100. Okay, so this is our unknown right now, we want to go ahead and figure that out. So the total mass. Well that that's going to give us the molar mass of X. PR four Is going to equal to so here we're gonna go ahead and divide those sides by 100. And then multiply both sides by .964. Right? So what we're going to get here for the total mass is 331.5 g. Right? So the total mass of the number on the bottom the X. That we didn't know we were not the X. But the unknown number. We just plug everything in and solve for that. And that gives us 3:31.5. So that is the molar mass of X. PR four. Now that we have the molar mass of that whole compound, we also know the total mass of bruning. If we subtract the massive grooming from the total mass of that compound, what's gonna be left over The massive X. rate. So that will be 11.9. And of course, that's in grams per mole because that's the molar masses. Right? So grams per mole for X. Now, if you take a look at the periodic table, the only element that's close enough to 11.9, we can of course just round it up to 12, it's going to be carbon. Right? So X actually equals two carbon. So our formula here would actually be C Br four. Okay, so the x element here is carbon, and that would be the full formula of this compound. Right, folks, thank you so much for watching, and we'll see you in the next video.

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1. Intro to General Chemistry3h 48m

Classification of MatterBonus
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19m

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10m

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11m

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4m

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9m

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13m

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6m

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8m

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5m

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4m

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23. Chemistry of the Nonmetals2h 39m

Main Group Elements: Bonding Types
4m

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7m

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11m

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7m

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16m

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20m

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22m

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3. Chemical Reactions

Mass Percent

General Chemistry

3. Chemical Reactions

Mass Percent

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A 69.5 g sample of the compound X₃O₄ contains 19.2 g of oxygen atoms. What is the molar mass of element X?

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A 69.5 g sample of the compound X₃O₄ contains 19.2 g of oxygen atoms. What is the molar mass of element X?