## Dumb_as_a_Duck 3 years ago Carbon and oxygen are known to form two compounds. The carbon content in one of these is 42.5 % while in other it is 27.3%. Show that this data is in agreement with the law of multiple proportions.

1. Dumb_as_a_Duck

What exactly do you do? :/

2. JFraser

Turn those percentages of each compound into mass, then into moles to find the 2 formulas of the compounds, and the formulas will be different. I'm guessing one formula is CO, while the other is CO2

3. Dumb_as_a_Duck

how do you get mass from percentage?

4. JFraser

If you assume you have 100g of each sample, then 42.5% of 100g is 42.5g of carbon. The rest of that sample must be made of oxygen. You could do it with any amount, but 100g is always easiest, since it turns the % into a mas with no math.

5. Dumb_as_a_Duck

I still dont see what this has to do with the problem in question.

6. Kryten

to solve this problem you must like JFraser said assume that you have same amount of each sample and its easier if you take 100 g of sample one and 100 g of sample 2 and then calculate further, get it now?

7. JFraser

2 compounds with different percentages of the same elements must possess different fomrulas, that's what the law of multiple proportions boils down to. Thep problem is asking you to find the formulas of the 2 compounds to show that they are different

8. Dumb_as_a_Duck

OOHHH okey. i got it :) thanks.