C(s) + s8(s) → cs2(l)

how many grams of carbon disulfide will be produced if 7.70 g of c and 19.7 g of s8 are allowed to react completely?

The balanced chemical reaction is written as:

4C(s) + S8(s) → 4CS2(l)

We are given the amount of carbon and sulfur to be used in the reaction. We need to determine first the limiting reactant to be able to solve this correctly.

7.70 g C ( 1 mol / 12.01 g) =0.64 mol C
19.7 g S8 ( 1 mol / 256.48 g) = 0.08 mol S8

The limiting reactant would be S8. We use this amount to calculate.

0.08 mol S8 ( 4 mol CS2 / 1 mol S8 ) ( 256.48 g / 1 mol ) = 78.8 g CS2

Mass of water is smething that you froma drug test or sum girl ya

The mass has escaped into a gas which you can not see so the law stays true.