Yield calculation help

Hey, I recently did a yield calculation question which I was told was calculated wrong. It was for a reaction of copper acetate with glycine to form copper glycine. Can you tell me where I went wrong?

Cu(CH3COO)2H2O + 2H2NCH2COOH → Cu(H2NCH2COO)2H2O + 2CH3COOH

Actual yield = 1.455g

Mass of copper (II) acetate = 1.598g

Moles of copper (II) acetate = 1.598/199.65 = 8.00 x 10-3 moles

Mass of glycine = 1.165 g

Moles of glycine = 1.165/75.07 = 0.0155 / 2 = 7.75 x 10-3 moles (Limiting reagent)

Theoretical yield = 7.75 x 10-3 x Mr Cu(gly)2H2O = 7.75 x 10-3 X 229.66 = 1.78g

% yield = 65.45%

You didn't say how you calculated the percentage yield, it should be actual yield divided by the theoretical yield then multiply by 100 to make it a percentage.

Yeah that was a silly mistake on my part. My demonstrator however says it's my theoretical yield that is incorrect, and I don't really know where?

I checked your calcs and it seems to be correct, are you sure your demonstrator didn't get it wrong?