Sam had 3 grams of aluminum to react with 16 grams of CuSO4 How many moles of pure copper could she recover

1. Write the equation and balance it.

2a. Convert 3 g Al to moles. moles = grams/molar mass.
2b. Do the same for the CuSO4.
3a. Using the coefficients in the balanced equation, convert moles Al to moles of the product.
3b. Same procedure, convert moles CuSO4 to moles of the product.
3c. It is quite likely that the moles of the product will be different for 3a and 3b and it must be obvious that one of them is wrong. The correct one, in limiting reagent problems like this, is ALWAYS the smaller value.
4. Convert the value from 3c to grams. grams = moles x molar mass.
Post your work if you get stuck.