Carbon disulfide, CS2 can be made from coke, C and sulfur dioxide, SO2: 3C + 2 SO2→ CS2 + CO2. If the actual yield of CS2 is 86% of the theoretical yield, what mass of coke is needed to produce 950g of CS2?

1 Answer
Jul 31, 2017

Answer:

#523# #"g C"#

Explanation:

Since #950# #"g"# is the desired mass of #"CS"_2#, and the percent yield is #86%#, the theoretical yield of #"CS"_2# is

#950# #"g CS"_2"# #xx 100/86 = ul(1107color(white)(l)"g CS"_2#

Now, let's convert this value to moles, using the molar mass of carbon disulfide:

#1107cancel("g CS"_2)((1color(white)(l)"mol CS"_2)/(76.14cancel("g CS"_2))) = color(red)(14.5# #color(red)("mol CS"_2#

Now, we use the coefficients of the chemical equation to find the relative number of moles of #"C"#:

#color(red)(14.5)cancel(color(red)("mol CS"_2))((3color(white)(l)"mol C")/(1cancel("mol CS"_2))) = color(green)(43.5# #color(green)("mol C"#

Finally, we use the molar mass of coke (carbon) to find the mass:

#color(green)(43.5)cancel(color(green)("mol C"))((12.011color(white)(l)"g C")/(1cancel("mol C"))) = color(blue)(ul(523color(white)(l)"g C"#