## Empirical and Molecular Formulas [ENDORSED]

thanh24mai
Posts: 50
Joined: Thu Jul 25, 2019 12:17 am

### Empirical and Molecular Formulas

Just to confirm, can the empirical formula and molecular formula be the same?

205296774
Posts: 66
Joined: Thu Jul 25, 2019 12:15 am

### Re: Empirical and Molecular Formulas

Yes, they can!

Jared Khoo 1G
Posts: 107
Joined: Wed Sep 18, 2019 12:16 am

### Re: Empirical and Molecular Formulas  [ENDORSED]

From the textbook, the empirical formula shows the relative number of atoms of each element in a compound by using the simplest whole-number subscripts. If you cannot simplify a molecular formula further, then it is also the empirical formula. An example is methane, which has both molecular formula and empirical formula CH4.

Posts: 58
Joined: Thu Jul 25, 2019 12:15 am

### Re: Empirical and Molecular Formulas

Yes they can! The empirical formula and molecular formula are the same if the ratios of the molecular formula cannot be reduced by any factor to smaller whole numbers.

Natalie Wang 1B
Posts: 51
Joined: Sat Sep 14, 2019 12:15 am
Been upvoted: 1 time

### Re: Empirical and Molecular Formulas

Also, a really handy trick with empirical and molecular formulas, is that if you're looking for the molecular formula of a compound, and you know the compound's molar mass (along with the empirical formula's molar mass), you can divide the compound's molar mass by the empirical formula's molar mass. Then, you can use that number to multiply with the subscripts of the empirical formula, which gives you the mystery compound's molecular formula.

605379296
Posts: 58
Joined: Sat Aug 17, 2019 12:16 am

### Re: Empirical and Molecular Formulas

As you may know, molecular formulas are a reduced form for empirical formulas. If molecular formulas can’t be reduced any further, that’s when the EF and MF are the same. For example, ethanol (C2H6O) can’t be reduced any further because there’s only one oxygen atom.