## Combustion Analysis

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MathematicalMistake
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Posts: 4
Joined: Sun Oct 08, 2023 6:38 pm

### Combustion Analysis

Polychlorinated biphenyls (PCBs) were once widely used industrial chemicals but were found to pose a risk to health and enviro- ment. PCBs contain only carbon, hydrogen, and chlorine. Aroclor 1254 is a PCB with mo- lar mass 360.88 g/mol. Combustion of 1.52 g of Aroclor 1254 produced 2.224 g of CO2, and combustion of 2.53 g produced 0.253 g of H2O. How many chlorine atoms does an Aroclor 1254 molecule contain?

The combustion equation is: CxHyClz + O2 -> CO2 + H2O + Cl2

ChenBeier
Distinguished Member
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Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Combustion Analysis

Calculate moles of Aroclor in both cases. Calculate the moles of CO2 and H2O and get the corresponding moles of C and H
The ratio of it gives the amount of C and H. From this you get the molar mass of CxHy . Subtraktion from the molar mass of Arcolor gives the molar mass off all chlorine, devide through the molar mass of chlorine gives the amount of chlorine,
MathematicalMistake
Newbie
Posts: 4
Joined: Sun Oct 08, 2023 6:38 pm

### Re: Combustion Analysis

Would the answer be 6 chlorine atoms? Is my math correct?
ChenBeier
Distinguished Member
Posts: 1420
Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Combustion Analysis

Correct.
And how many C and H?