[yellow_jello]

Hi! I'm reeeallly bad at chem and need some help with a pre-lab question dealing with percent yield.
Copper dissolves in nitric acid, producing copper (II) nitrate. After raction with sodium hydroxide and heating, copper nitrate changes to copper (II) oxide. Calculate the percent yield of this process if 1.235g of copper produced 1.452g of copper oxide.
If anyone can help it would be greatly appreciated!!

[LQ43]

Can you at least write a balanced equation of

Cu +  _?__    --->  copper (II) oxide

[yellow_jello]

Based on the question, to get copper (II) oxide wouldn't you have to have an equation like this 2Cu(NO3)2 = 2CuO + 4NO2 + O2 ...

[LQ43]

think about following the Cu around as it goes through these reactions

all the Cu that you start with ends up as copper (II) oxide

although its good to write an equation for each step of the process, for the purposes of the stoichiometry that your question is asking, you can look at the Cu metal that you started with and the copper (II) oxide that you end with (and for now, ignore all the reagents in the middle)

so what do you need to react with Cu to get copper (II) oxide

Cu  +  ___   --->  CuO

be sure to balance

[yellow_jello]

oh ok.. so ... 2Cu + O2= 2CuO

[enahs]

So how much did you start with? How much did you end up with? How much could you have theoretically made based on how much you started with? What is the percent yield for those numbers?