# Answer to Question #25722 in Inorganic Chemistry for chem

Question #25722
Polychlorinated biphenyls (PCB) are environmental and health hazard. They break down very slowly in the environment. The decomposition of PCBs can be represented by the equation:

2 C12H4Cl6 + 23 O2 + 2 H2O --&gt; 24 CO2 + 12 HCl

a) How many moles of water are needed to react 10.0 mol PCB?

b) How many grams of HCl are produced when 15.2 mol H2O react?

c) How many moles of CO2 are produced when 76.5g HCl are produced?

d) How many grams of PCB are reacted when 100.25g CO2 are produced?

e) How many grams of HCl are produced when 2.5kg of PCB react?
1
2013-03-12T12:38:41-0400
2C12H4Cl6 + 23O2 + 2H2O = 24CO2 + 12HCl

a) How many moles of water are needed to react 10.0 mol PCB?
According to equation
n(H2O) = n(PCB) = 10.0 mol

b) How many grams of HCl are produced when 15.2 mol H2O react?
According to equation the amount of HCl is
n(HCl) = 6 x n(H2O) = 6 x 15.2 = 91.2 mol
The weight of HCl is
m(HCl) = n(HCl) x MW(HCl) = 91.2 x ( 1+ 35.5) = 3328.8 g

c) How many moles of CO2 are produced when 76.5g HCl are produced?
n(HCl) = m(HCl) / MW(HCl) = 76.5 / 36.5 = 2.10 mol
According to equation
n(CO2) = 2n(HCl) = 2 x 2.10 = 4.20 mol

d) How many grams of PCB are reacted when 100.25g CO2 are produced?
MW(PCB) = 12 x 12 + 4 x 1 + 6 x 35.5 = 361 g/mol
n(CO2) = m(CO2) / MW(CO2) = 100.25 / 44 = 2.28 mol
According to equation
n(PCB) = n(CO2) / 12 = 2.28 /12 = 0.19 mol
m(PCB) = n(PCB) x MW(PCB) = 0.19 x 361 = 68.59 g

e) How many grams of HCl are produced when 2.5kg of PCB react?
n(PCB) = m(PCB) / MW(PCB) = 2500 / 361 = 6.93 mol
According to equation
n(HCl) = 6n(PCB) = 6 x 6.93 = 41.58 mol
m(HCl) = n(HCl) x MW(HCl) = 41.68 x 36.5 = 1517.7 g

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Assignment Expert
21.03.16, 16:41

Dear visitor, please use panel for submitting new questions

pooh
21.03.16, 04:18

The molar mass of glucose is 180.15 g/mol, the molar mass of ethanol is 46.08 g/mol, and the molar mass of carbon dioxide is 44.01 g/mol. a) What is the theoretical yield (in grams) of ethanol from the fermentation of 75.0 g of glucose?