A tank holds 2.85 L of oxygen at 22.1 Celsius and 235 atm. (A) how many moles of gas does the tank contain? (B) what is the average kinetic energy per molecule ?
the answer in the text book is (a) 27.7 moles (b) 2.381x10^7pa
i just want the formula so i can attempt the problem myself so i can plug it in
I seem to recall answering this problem already. I used the fact that one mole at STP occupies 22.4 liters, and scaled for the pressure and temperature change from STP. In (B), the units of kinetic energy are not Pascals
To calculate the number of moles of gas in the tank, you can use the ideal gas law equation:
PV = nRT
where:
P = pressure (in atm)
V = volume (in L)
n = number of moles
R = ideal gas constant (0.0821 L·atm/(mol·K))
T = temperature (in Kelvin)
To convert the temperature from Celsius to Kelvin, simply add 273.15.
(A) To find the number of moles, we rearrange the equation:
n = PV / RT
Now you can substitute the given values:
P = 235 atm
V = 2.85 L
R = 0.0821 L·atm/(mol·K)
T = (22.1 + 273.15) K
Plug these values into the equation to calculate n.
(B) The average kinetic energy per molecule can be calculated using the following formula:
KE_avg = (3/2) * R * T
where:
R = ideal gas constant
T = temperature (in Kelvin)
Again, you can substitute the given values and calculate the result.
Please keep in mind that when performing calculations, it's essential to use the appropriate units and to convert values if necessary (e.g., Celsius to Kelvin).