An experiment being conducted, the pressure is 0.9 atm and the temperature is 18 ° C. One of the steps of
experience requires the combustion of 500 ml of ethanol (d = 0.78 g / ml). Whereas the burning this amount of ethanol does not significantly alter the enviroments conditions, but releases carbon dioxide. Calculate the volume of CO2 generated (in L) and the CO2 concentration in mol / L
To calculate the volume of CO2 generated and the CO2 concentration in mol/L, we need to follow a few steps.
Step 1: Convert the volume of ethanol from milliliters (mL) to liters (L).
500 mL = 500/1000 = 0.5 L
Step 2: Convert the mass of ethanol from grams (g) to moles (mol).
To do this, we need to know the molar mass of ethanol, which is C2H5OH. The molar masses of carbon (C), hydrogen (H), and oxygen (O) are 12.01 g/mol, 1.01 g/mol, and 16.00 g/mol, respectively.
C2H5OH = 2(C) + 6(H) + 1(O) = 2(12.01) + 6(1.01) + 16.00 = 46.07 g/mol
Now, we can calculate the number of moles of ethanol.
Number of moles = mass/molar mass
Number of moles = (0.5 L) x (0.78 g/mL) / (46.07 g/mol)
Step 3: Calculate the number of moles of CO2 produced.
Ethanol undergoes complete combustion to produce carbon dioxide (CO2) and water (H2O) according to the balanced chemical equation:
C2H5OH + 3O2 → 2CO2 + 3H2O
From the equation, we can see that 2 moles of CO2 are produced for every 1 mole of ethanol burned. So, the number of moles of CO2 produced is:
Number of moles of CO2 = 2 x Number of moles of ethanol
Step 4: Convert moles of CO2 to volume in liters.
To do this, we need to know the ideal gas law, which states:
PV = nRT
Where:
P = pressure (0.9 atm)
V = volume (unknown)
n = number of moles (from Step 3)
R = ideal gas constant (0.0821 L.atm/mol.K)
T = temperature in Kelvin (18°C + 273.15 = 291.15 K)
Rearranging the equation, we get:
V = nRT/P
Step 5: Calculate the volume of CO2 generated.
V = (Number of moles of CO2) x (R) x (T) / P
Plug in the values:
V = (2 x Number of moles of ethanol) x (0.0821 L.atm/mol.K) x (291.15 K) / 0.9 atm
Step 6: Convert the volume of CO2 generated from liters (L) to milliliters (mL).
1 L = 1000 mL
Finally, we can calculate the CO2 concentration in mol/L. The concentration is the number of moles divided by the volume in liters.
I hope this step-by-step explanation helps you in getting the answer to your question.