How to Find the Percent Composition by Mass for C2H6 (Ethane)

To find the percent composition (by mass) for each element in C2H6 we need to determine the molar mass for each element and for the entire C2H6 compound.

We’ll use the following formula for percent composition by mass:

Percent Composition by Mass = (Molar Mass of Element x Number of that Element)/ Molar Mass of Compound

In this video I’m using a Periodic Table that rounds to two decimal places. You may be asked to use a Periodic Table with more decimal places, however the process to find the percent composition by mass is the same.

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Note that if you add up the percentages for all of the elements it should be close to 100%. Often it will not be exact to the rounding of the atomic mass for elements.

Note: C2H6 is also known as Ethane.

[emmarust]

This was so easy to follow under your directions. I was overthinking it way too hard, goodness. Thank you, sir

[Chapelron]

Ah now i understand whats going on, i swear my teacher does not tell us any basic formulas. Thanks.

[jayanthkumar]

Thanks a lot for helping me from problem clearly 👍👍👍

[meetgajjar]

Sir, which is your most favourite topic in Chemistry?

[MahwishIlyas-lmyv]

0.75g of a hydrocarbon compound contain o.60g of carbon which could be the molecular for mila of compound c2H6 CH4. C3H8.

[donutzzs]

Tq sir can u make video for definition for polar bonds ionic bonds what is electronegetivity, how to calculate electronegetivity, difference of I AM ASKING SOME NOTES/DETIAL INFORMATION ABOUT THE CHEMICAL BONDING CHAPTER. :)

[Suzuchikuma]

Well C2H6 is ethane...
Ethene is C2H4

[pndgetsmewet]

how did you got 20.15%? cause i always get 20.14%