Midterm Practice Problem #1

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Dominique S 4E
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Joined: Fri Sep 28, 2018 12:27 am

Midterm Practice Problem #1

Postby Dominique S 4E » Sat Nov 03, 2018 8:09 pm

Isopropyl alcohol, used in rubbing alcohol, is a compound containing only C, H, and O. What is the empirical formula of isopropyl alcohol if you find that 0.255 g of the compound gives 0.561g of CO2 and 0.306 g of H2O when burned completely in excess oxygen?

Schuyler_Howell_4D
Posts: 66
Joined: Fri Sep 28, 2018 12:28 am
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Re: Midterm Practice Problem #1

Postby Schuyler_Howell_4D » Sat Nov 03, 2018 8:42 pm

General steps:

1)Convert grams of each element into moles of the element
2)Take moles of each element and multiply by the ratio of that element in the molecule (1 C/ 1 CO2) so that you get grams of the individual element
3) Take those grams from step 2 and convert from grams of the element to mols of element
4)Divide by the smallest moles to get mole ratio
5) Create Molecular formula

ArielKim3C
Posts: 30
Joined: Fri Sep 28, 2018 12:25 am

Re: Midterm Practice Problem #1

Postby ArielKim3C » Sat Nov 03, 2018 8:56 pm

Here's the work too if you wanted to see what numbers to use and such!
Attachments
IMG_5678.JPG


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