I can help but can you post a picture of what the equation really looks like?? message me if you need to.
The SI base unit for amount of substance is the mole. 1 grams KCl is equal to 0.013413582325191 mole.
Oxygen is colorless odorless and tasteless so it has no texture
It has 1 valence electron.
Calculating the number of mole of COSO4 reacted
=mass/R.F.M
R.F.M of CUSO4 is 63.54+32+64=159.6
moles is therefore 200g/159.54=1.254moles
since reacting ratio is 1:1 ,moles of Cu is also 1.254moles
mass is therefore moles x R.F.M
1.254x63.54=79.6g(answer C)