Question

Carbon disulfide (CS2) reacts with excess chlorine (Cl2) to produce carbon tetrachloride (CCl4) and disulfur dichloride (S2Cl2). If 64.9 g of CS2 yields 73.1 g of CCl4, what is the percent yield? (Hint, you must first write the balanced equation.)

Answer 1

Molar mass of CS2,
MM = 1*MM(C) + 2*MM(S)
= 1*12.01 + 2*32.07
= 76.15 g/mol


mass(CS2)= 64.9 g

number of mol of CS2,
n = mass of CS2/molar mass of CS2
=(64.9 g)/(76.15 g/mol)
= 0.8523 mol

Balanced chemical equation is:
CS2 + 4 Cl2 ---> CCl4 + 2 S2Cl2
  

Molar mass of CCl4,
MM = 1*MM(C) + 4*MM(Cl)
= 1*12.01 + 4*35.45
= 153.81 g/mol

According to balanced equation
mol of CCl4 formed = (1/1)* moles of CS2
= (1/1)*0.852265
= 0.8523 mol


mass of CCl4 = number of mol * molar mass
= 0.8523*1.538*10^2
= 1.311*10^2 g

% yield = actual mass*100/theoretical mass
= 73.1*100/1.311*10^2
= 55.8 %

Answer: 55.8 %