Quiz 1 Last Question Help  [ENDORSED]

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Kristen Laulette 1C
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Joined: Fri Apr 06, 2018 11:03 am

Quiz 1 Last Question Help

Postby Kristen Laulette 1C » Sun Apr 15, 2018 10:49 pm

On the quiz, we were given element diagrams on the last problem where we had to determine the empirical and molecular formula. When finding the molecular formula based on the atom diagram, since I've heard you should do that first, do you count the amount of atoms of each molecule and then put that into the molecular formula?

If so, to find out the empirical formula from that, do you find a ratio and simplify it? Or how would you go about these problems? I'm still confused onto how.

Corryn Doll
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Joined: Fri Apr 06, 2018 11:02 am

Re: Quiz 1 Last Question Help

Postby Corryn Doll » Sun Apr 15, 2018 11:04 pm

So to do these problems it is easiest to find the molecular formula first by counting the amount of atoms of each element and writing the formula out from that. Because the molecular formula is the formula that contains the actual number of the atoms, it can be created simply by counting the number of each element. To find the empirical formula, you want to find the smallest possible ratio of the molecular formula.

For example, if given an molecule with 12 Hydrogen, 6 Carbon, and 3 Oxygen then your molecular formula would be H12C6O3. Your empirical formula would then be H4C2O, because each element can be divided by 3.

Hope this helped!

Corryn Doll
Posts: 31
Joined: Fri Apr 06, 2018 11:02 am

Re: Quiz 1 Last Question Help  [ENDORSED]

Postby Corryn Doll » Sun Apr 15, 2018 11:06 pm

One more thing. If you write out your molecular formula and find that it cannot be reduced as a ratio any more than you can write the same for the empirical formula as they can be the same.

Jennifer 1G
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Joined: Wed Nov 15, 2017 3:03 am

Re: Quiz 1 Last Question Help

Postby Jennifer 1G » Sun Apr 15, 2018 11:19 pm

On the website, there is a video posted about this topic. I think it mentioned that at empirical formula was the ratio of the molecular formula. It sounds like we took similar steps. Although I'm not exactly sure if I did this right, I counted the total of each element and wrote the molecular formula from that, and reduced for the empirical formula.


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