What mass of CO2, a greenhouse gas, is produced per liter of each fuel (assuming complete combustion)
I got this data
density of ethanol = 0.785 g/mL
density of octane = 0.699 g/mL
Ethanol) C2 H5 OH + 2O2 -> 2CO2 + 3H2O
delta H combustion ethanol = -1234.8 Kj/mol
Octane) C8H18 + (25/2)O2 -> 8CO2 + 9H2O\
delta H combustion = -5074.3 KJ/mol
thanks!
Figure the liters of CO2 due to ethanol, well you get as you stated, two moles of co2 for each mole of ethanol, so ..
molesethanol= 1liter*785g/liter*1moleethanol/molmassethanol.
so figure that out, then twice that is the moles of CO2, and figure about 24liters /mole
Now do the same technique for the nine liters of octane.
To find the mass of CO2 produced per liter of each fuel, we will need to calculate the number of moles of CO2 produced in each reaction and then convert it to mass.
First, let's calculate the number of moles of CO2 produced in the combustion of ethanol:
1 mole of ethanol (C2H5OH) produces 2 moles of CO2 according to the balanced equation.
We can use the molar mass of ethanol to convert from grams of ethanol to moles. The molar mass of ethanol is:
2(12.01 g/mol) + 5(1.01 g/mol) + 16.00 g/mol = 46.07 g/mol
So, 46.07 g of ethanol is equal to 1 mole of ethanol.
Now, we can use the given density of ethanol to convert from volume (1 L) to mass (grams). The density of ethanol is 0.785 g/mL, so:
1 L ethanol = 1,000 mL ethanol
= 1,000 mL ethanol * 0.785 g/mL
= 785 g ethanol
Next, we can calculate the number of moles of CO2 produced:
1 mole of ethanol = 2 moles of CO2
1 mole of ethanol produces 46.07 g of CO2
So, using the unitary method:
785 g ethanol * (2 moles CO2 / 46.07 g ethanol)
= 34.0 moles of CO2
Finally, we can convert the number of moles of CO2 to grams by using the molar mass of CO2 (44.01 g/mol):
34.0 moles CO2 * 44.01 g/mol = 1494 g of CO2
Therefore, approximately 1494 grams of CO2 are produced per liter of ethanol.
Now, let's calculate the mass of CO2 produced per liter of octane:
Using a similar calculation, we can first find the number of moles of CO2 produced in the combustion of octane:
1 mole of octane (C8H18) produces 8 moles of CO2.
The molar mass of octane is:
8(12.01 g/mol) + 18(1.01 g/mol) = 114.22 g/mol
So, 114.22 g of octane is equal to 1 mole of octane.
We can use the given density of octane to convert from volume (1 L) to mass (grams). The density of octane is 0.699 g/mL, so:
1 L octane = 1,000 mL octane
= 1,000 mL octane * 0.699 g/mL
= 699 g octane
Next, we can calculate the number of moles of CO2 produced:
1 mole of octane = 8 moles of CO2
1 mole of octane produces 114.22 g of CO2
Using the unitary method:
699 g octane * (8 moles CO2 / 114.22 g octane)
= 48.6 moles of CO2
Finally, we can convert the number of moles of CO2 to grams:
48.6 moles CO2 * 44.01 g/mol = 2139 g of CO2
Therefore, approximately 2139 grams of CO2 are produced per liter of octane.
In summary:
- For ethanol, approximately 1494 grams of CO2 are produced per liter.
- For octane, approximately 2139 grams of CO2 are produced per liter.