need some chem help

[Kevin1211]

takin intro to chem here in college. I took AP chem in 11th grade highschool, so i dont remember a lot. But im totally lost in this problem

.500g of Cu2O + CuO contains 0.425g Cu. What is the mass of CuO in mixture

i honestly dont know how to go about solving it. Im lost.. (

 

[hypn0tik]

It's a purely mathematical problem

 

[Ika]

Not sure about this, but try:

find the molar masses of both Cu2O + CuO, then find the number of moles of Cu from the mass given. Then find the total number of moles, and moles of CU:moles of O should be 3:2, so you can figure out how many moles of O there are. I lost myself, but work that out???

 

[hypn0tik]

Originally posted by: Aflac
Not sure about this, but try:

find the molar masses of both Cu2O + CuO, then find the number of moles of Cu from the mass given. Then find the total number of moles, and moles of CU:moles of O should be 3:2, so you can figure out how many moles of O there are. I lost myself, but work that out???

Too much unnecessary work.

Edit:

You know the mass of Cu = 0.425g. The mass of O must be .5-.425 = 0.075g.

Try it from there.