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Chemistry help needed for question!!!

For the reaction of complete combustion of liquid cyclohexane:


C6H12 (l) + 9O2 (g) -> 6CO2 (g) + 6H2O (g)


The mass density of liquid cyclohexane is p = 779 kg m-3 and the molar heat of complete combustion of the liquid cyclohexane is -3920 kJ mol-1.


Determine how many litres of CO2(g) measured at 160oC and pressure 900 mmHg are produced in the complete combustion of 450 mL of liquid cyclohexane, C6H12(l)?

If you guys could help me, that would be fantastic!!! :colondollar:
Original post by Natty-sgw
For the reaction of complete combustion of liquid cyclohexane:


C6H12 (l) + 9O2 (g) -> 6CO2 (g) + 6H2O (g)


The mass density of liquid cyclohexane is p = 779 kg m-3 and the molar heat of complete combustion of the liquid cyclohexane is -3920 kJ mol-1.


Determine how many litres of CO2(g) measured at 160oC and pressure 900 mmHg are produced in the complete combustion of 450 mL of liquid cyclohexane, C6H12(l)?

If you guys could help me, that would be fantastic!!! :colondollar:


Moved to the chemistry forum for you :hat2:

I'm sure someone will be able to help you here:h:
Original post by Natty-sgw
For the reaction of complete combustion of liquid cyclohexane:


C6H12 (l) + 9O2 (g) -> 6CO2 (g) + 6H2O (g)


The mass density of liquid cyclohexane is p = 779 kg m-3 and the molar heat of complete combustion of the liquid cyclohexane is -3920 kJ mol-1.


Determine how many litres of CO2(g) measured at 160oC and pressure 900 mmHg are produced in the complete combustion of 450 mL of liquid cyclohexane, C6H12(l)?

If you guys could help me, that would be fantastic!!! :colondollar:


Convert litres of cyclohexane into mass using

dentistry = mass/volume

Convert mass to moles using

moles = mass/relative mass

Use the stoichiometry of the equation to find moles of carbon dioxide produced.

Use the ideal gas equation PV=nRT to convert moles to volume of carbon dioxide ...
Reply 3
Avatar for Natty-sgw
Natty-sgw
OP
Thank you!!!!

Original post by charco
Convert litres of cyclohexane into mass using

dentistry = mass/volume

Convert mass to moles using

moles = mass/relative mass

Use the stoichiometry of the equation to find moles of carbon dioxide produced.

Use the ideal gas equation PV=nRT to convert moles to volume of carbon dioxide ...
Original post by charco
Convert litres of cyclohexane into mass using

dentistry = mass/volume

Convert mass to moles using

moles = mass/relative mass

Use the stoichiometry of the equation to find moles of carbon dioxide produced.

Use the ideal gas equation PV=nRT to convert moles to volume of carbon dioxide ...

I know this is off topic but you seem knowledgeable so can you also help me?
Original post by SwaggerDagger
I know this is off topic but you seem knowledgeable so can you also help me?


with what????
Original post by charco
with what????

Assume the compounds below only contain C and H.
What is the empirical formula of each of the following compounds?
Complete combustion of 1g of a compound produced 2.99g CO2 and 1.64g H2O
Original post by SwaggerDagger
Assume the compounds below only contain C and H.
What is the empirical formula of each of the following compounds?
Complete combustion of 1g of a compound produced 2.99g CO2 and 1.64g H2O


Divide each by it's relative mass..

Then divide the two results by the smaller number ..

If you dont have two integers at this point multiply both numbers by any value that gives integers.
Original post by charco
Divide each by it's relative mass..

Then divide the two results by the smaller number ..

If you dont have two integers at this point multiply both numbers by any value that gives integers.

Is the answer C3H4 right?
Original post by SwaggerDagger
Is the answer C3H4 right?


CO2 = 2.99g

carbon content = 2.99/44 mol = 0.068

H2O = 1.64g

hydrogen content = 2 x 1.64/18 = 0.182 mol

Divide both by 0.068

carbon = 1
hydrogen = 2.67

multiply both by 3

carbon = 3
hydrogen = 8

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