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 58m

Classification of Matter
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Physical & Chemical Changes
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Chemical Properties
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Physical Properties
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41m

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32m

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Third Law of Thermodynamics
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20m

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10m

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9m

Neutron to Proton Ratio
7m

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10m

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3m

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4m

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14m

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7m

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12m

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16m

Mass Defect
19m

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14m

22. Organic Chemistry5h 4m

Introduction to Organic Chemistry
8m

Structural Formula
8m

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10m

Skeletal Formula
6m

Spatial Orientation of Bonds
3m

Intro to Hydrocarbons
16m

Isomers
11m

Chirality
12m

Functional Groups in Chemistry
11m

Naming Alkanes
4m

The Alkyl Groups
9m

Naming Alkanes with Substituents
13m

Naming Cyclic Alkanes
6m

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8m

Naming Alcohols
11m

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11m

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9m

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5m

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5m

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4m

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8m

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5m

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5m

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7m

Alkane Reactions
7m

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4m

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4m

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3m

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7m

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4m

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9m

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8m

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7m

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6m

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4m

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3m

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3m

Amide Formation
4m

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10m

23. Chemistry of the Nonmetals2h 39m

Main Group Elements: Bonding Types
4m

Main Group Elements: Boiling & Melting Points
7m

Main Group Elements: Density
11m

Main Group Elements: Periodic Trends
7m

The Electron Configuration Review
16m

Periodic Table Charges Review
20m

Hydrogen Isotopes
4m

Hydrogen Compounds
11m

Production of Hydrogen
8m

Group 1A and 2A Reactions
7m

Boron Family Reactions
7m

Boron Family: Borane
7m

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7m

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12m

Oxides, Peroxides, and Superoxides
12m

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4m

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6m

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24. Transition Metals and Coordination Compounds3h 19m

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11m

Electron Configurations of Transition Metals
7m

Electron Configurations of Transition Metals: Exceptions
11m

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10m

Ligands
10m

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5m

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7m

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11m

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9m

Naming Coordination Compounds
22m

Writing Formulas of Coordination Compounds
8m

Isomerism in Coordination Complexes
17m

Orientations of D Orbitals
4m

Intro to Crystal Field Theory
10m

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5m

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4m

Crystal Field Theory Summary
8m

Magnetic Properties of Complex Ions
9m

Strong-Field vs Weak-Field Ligands
6m

Magnetic Properties of Complex Ions: Octahedral Complexes
11m

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?

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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?