empirical formula

[gyytyg]

14.3g of an oxide of copper contained 12.7g of copper

calculate the empirical formula of this oxide

relative formula masses Cu= 63.5 O=16

please help this is what I done

 

12.7/63.5= 0.2 I am not sure about the rest

Edited January 30, 2017 by gyytyg

[Sensei]

14.3g of an oxide of copper contained 12.7g of copper

calculate the empirical formula of this oxide

relative formula masses Cu= 63.5 O=16

please help this is what I done

How many Copper oxides do you know?

 

How to calculate molar mass of compound?

 

How to calculate percentage of one element in compound?

 

12.7/63.5= 0.2 I am not sure about the rest

It's not correct.

[dill]

If the 14.3 gram compound contains only copper and oxygen atoms and 12.7 grams of it is copper, how much of it is oxygen (in grams)? With that, how many times more copper than oxygen is there in the compound? Now, the atomic mass of copper is how many times greater than the atomic mass of oxygen?... Knowing these two ratios, you should be able to determine the ratio of copper to oxygen atoms in the compound to get the empirical formula!