Creating a molecular/empirical formula

Zuri Smith 1A
Posts: 34
Joined: Fri Apr 06, 2018 11:05 am

Creating a molecular/empirical formula

When given the actual physical structure of a molecule, how do we construct the molecular/empirical formulas? I.e., if we are given a structure in which there are five Carbon and Hydrogen atoms paired together, and connected by bonds, would the equation be 5(CH)? Or (CH) subscript 5?

Sunjum Singh 1I
Posts: 30
Joined: Fri Apr 06, 2018 11:05 am

Re: Creating a molecular/empirical formula

For molecular formula you count how many atoms there are of each, so in your example it would be C5 and depending on the amount of H atoms in the model it would be H(however many H atoms). To find empirical from there you find a number that could go into each subscript and still be left with a whole number. So for example C6H12O2 has a common number of 2, so you divide by 2 to get C3H6O to be the empirical formula.

Chem_Mod
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Re: Creating a molecular/empirical formula

The molecular formula would be C5H5. The empirical formula would be CH

KristinaNguyen_1A
Posts: 30
Joined: Fri Apr 06, 2018 11:04 am

Re: Creating a molecular/empirical formula

The molecular formula would be C5H5 because the model gives the actual amount. You will then try to figure out if you can simplify it and because both are divisible by 5, you divide it by five to get the empirical formula of CH.