Final answer:
To produce 500 grams of CuSO4, 445.03 grams of Na2SO4 are required, based on stoichiometric calculations using the molar masses and a balanced chemical reaction.
Step-by-step explanation:
To determine how many grams of Na2SO4 are needed to combine with excess CuCl2 to produce 500 g of the green pigment CuSO4, we need to use stoichiometry. First, we must write the balanced chemical equation, which in this case is:
Na2SO4 + CuCl2 → CuSO4 + 2 NaCl
From the equation, we can see that one mole of Na2SO4 reacts with one mole of CuCl2 to produce one mole of CuSO4. Since the molar mass of CuSO4 is 159.62 g/mol, we can calculate the moles of CuSO4 in 500 g:
Moles of CuSO4 = 500 g / 159.62 g/mol
= 3.133 moles
Since the reaction ratio is 1:1, 3.133 moles of Na2SO4 are also needed. The molar mass of Na2SO4 is approximately 142.04 g/mol, and therefore:
Mass of Na2SO4 needed = 3.133 moles × 142.04 g/mol
= 445.03 g
Thus, 445.03 grams of Na2SO4 are required to produce 500 grams of CuSO4.