Air entering the lungs ends up in tiny sacs called alveoli. It is from the alveoli that oxygen diffuses into the blood. The average voume of the alveoli is .00000000078 L. Assuming that the pressure in the alveoli is 1.0 atm and the temperature is 37 degrees celsius, calculate the number of moles of air in one of the alveoli.
I used n=PV/RT but for someone reason it keeps telling me i have the wrong answer
I can't tell what your work is if you don't post it. If you will post your work I will look for the error. A common mistake beginners make is to use T in celsius and not convert to Kelvin.
i used .00000000078L for volume 1.0atm for pressure 310k for temperature and 0.0821 for R. The answer i got was 2.945 but that's not correct
n=PV/RT
n = (1.0 x 7.8 x 10^-10)/(0.0821*310) = 3.06 x 10^-11. You only missed it by a factor of 100 billion.
To calculate the number of moles of air in one of the alveoli, you can use the ideal gas equation:
PV = nRT
where:
P = pressure (in atm)
V = volume (in liters)
n = number of moles
R = ideal gas constant (0.0821 L·atm/mol·K)
T = temperature (in Kelvin)
In this case, you are given:
P = 1.0 atm
V = 0.00000000078 L
R = 0.0821 L·atm/mol·K
T = 37 degrees Celsius
However, to use the ideal gas equation, the temperature needs to be in Kelvin. So we need to convert Celsius to Kelvin. The conversion is done by adding 273.15 to the Celsius temperature:
T (in Kelvin) = 37 + 273.15 = 310.15 K
Now we can plug in the values into the equation:
n = PV/RT
= (1.0 atm) * (0.00000000078 L) / (0.0821 L·atm/mol·K * 310.15 K)
Simplifying:
n ≈ 0.00000000002363 mol
So, the number of moles of air in one of the alveoli is approximately 0.00000000002363 mol.