[marebare]

can anyone explain empirical formula for me, i just dont get it , looked it up on wikipedia but cant make much sense of it. i have lab question that asks the empirical formula for acetic acid

[Arkcon]

If you search these forums, you'll get a good idea.  Dunno if it's a better explanation the wikipedia, but you'll let us know.

[Controlled Substance]

Empirical Formula vs Molecular Formula.

One of them tells you the exact amount of each element present in a compound.
The other one only tells you the ratio of each element present in a compound.

Figure out which is which and you're set.

[Arkcon]

EDIT: DAMMIT ... admin please fix my username   

I like it better this way, makes it look like you're being deliberately ironic.

[Borek]

EDIT: DAMMIT ... admin please fix my username

You can do it by yourself, in your profile.

[Controlled Substance]

EDIT: DAMMIT ... admin please fix my username

You can do it by yourself, in your profile.

Thank you.

[DrCMS]

Back to the original question of Empirical Formula.

Here is an example for hydrogen peroxide

Molecular formula = H₂O₂ (actual structural formula)

Emperical formula = HO (just the ratios)

Does that make sense now?

[Shinigami_lover]

emperical formula- formula of a substance written with the smallest integer (whole number) subscripts.

here's an example:

a sample weighing 1.587 g is found in .483 g Nitrogen
and 1.104 g Oxygen.

1. You first start of by changing the grams into mole. You can do this by diving the grams givin by the atomic weight. in this case, Nitrogen = 14 and Oxygen = 16.

this leaves you with this
.483/14 = .0345 moles of Nitrogen
and
1.104/16 = .06900 moles of Oxygen

2. take the smallest numer (in this case .0345) and divide it by both numbers

this should look like
(Nitrogen) .0345/.0345 = 1
and
(Oxygen) .06900/.0345 = 2

3. the ratio of N atoms to the number of O atoms is 1 and 2. Hence the answer is

NO2

hope I helped,
Shinigami