A two-liter plastic soft drink bottle can withstand a pressure of 5.00 atm. Half a cup (approximately 120mL) of ethyl alcohol, (d=0.789g/mL) is poured into a soft drink bottle at room temperature. The bottle is then heated to 100C (3sig figs), changing the liquid alcohol to a gas. What is the pressure caused by the gas?
Pf= 4.65(.120)/297 x 373/.120 = 5.84
Can some one let me know if this is correct
Use:
PV = nRT
n = number of moles
Find the mass of ethyl alcohol = Density x Volume in mLs
Divide the mass by 1 mole C2H5OH --> n
R = 0.0821 L.atm/K.mol
T = 273 + 100 = 373K
L = 2.00 L
Substitute and solve for P
1 mole of C2H5OH = 12.011•2 + 1.00794•6 + 16.00 = 46.07 grams
First of all, density is mol./L. Therefore L x D will give you n. Then you plug in the numbers into P=nRT/V
To calculate the pressure caused by the gas, you can use the ideal gas law equation:
PV = nRT
Where:
P = pressure
V = volume
n = number of moles
R = ideal gas constant
T = temperature
First, let's calculate the number of moles of ethyl alcohol (C2H5OH) that are in half a cup (120 mL):
Number of moles (n) = volume (V) / molar mass (M)
The molar mass of ethyl alcohol (C2H5OH) can be calculated as:
Molar mass (M) = (2 x Molar mass of carbon) + (6 x Molar mass of hydrogen) + Molar mass of oxygen
Next, calculate the molar mass of carbon (C), hydrogen (H), and oxygen (O) from the periodic table. Then, substitute those values into the equation:
Molar mass of C = 12.01 g/mol
Molar mass of H = 1.01 g/mol
Molar mass of O = 16.00 g/mol
M = (2 x 12.01) + (6 x 1.01) + 16.00
Once you have the molar mass, you can calculate the number of moles:
n = V / M
Substitute the given values:
V = 120 mL = 0.120 L (converted to liters)
M = calculated molar mass
Now, you can calculate the pressure:
P = (nRT) / V
You already have the value of R, which is the ideal gas constant.
T = 100°C = 373 K (converted to Kelvin)
Substitute all the known values into the equation and solve for P:
P = (nRT) / V
Verify that all units are consistent (moles, liters, Kelvin, and atmospheres) before performing the calculation.
After calculating the pressure, compare it to the given value of 5.00 atm. If the calculated pressure matches the given value, then your calculation is correct.