Molecular Formula

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Algernon Jackson 2l
Posts: 52
Joined: Mon Jan 06, 2020 7:27 am

Molecular Formula

Postby Algernon Jackson 2l » Sun Oct 11, 2020 2:18 pm

What is the easiest way to find the common multiple that you multiply the molar masses by to get the molecular formula?

abby hyman
Posts: 93
Joined: Thu Jul 25, 2019 12:16 am

Re: Molecular Formula

Postby abby hyman » Sun Oct 11, 2020 2:45 pm

Although the molecular formula is directly related to the molar mass of elements and the compound, there is not a common multiple that would take you from molar mass to molecular formula. If you meant how to get from empirical formula to molecular formula using the total molar mass, then you would add up the molar masses of the elements from the empirical formula and divide the total by the molar mass given in the question and determine the ratio between the two to figure out what to multiple the empirical formula by

Natalie 3k
Posts: 91
Joined: Wed Sep 30, 2020 10:11 pm

Re: Molecular Formula

Postby Natalie 3k » Sun Oct 11, 2020 3:23 pm

You have to find the molar mass of the empirical formula and the molar mass of the molecular formula and then find the ratio between them. Then you multiply that by the number of atoms in the empirical formula. So if the molar mass of the molecular formula is 3x as much as the molar mass of the empirical formula you know each element has 3x as what is shown in the empirical formula.

jasmineculilap_3F
Posts: 95
Joined: Wed Sep 30, 2020 9:40 pm

Re: Molecular Formula

Postby jasmineculilap_3F » Sun Oct 11, 2020 3:28 pm

Once you find the empirical formula's molar mass, you can divide the mass of the molecular formula by the empirical formula to get the ratio. You can then use that number and multiply each element's subscript/number of atoms in the empirical formula by that number to get the molecular formula.


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