Calculate the translational kinetic energy of O2 at
a) 300. K
b) 1000. K
Speed is not given. Do I need to find the average speed first?
The formula I'm using is
Ek= 1/2m v^2
I notice I'm not given mass in the problem either. Would I use molar mass?
You are on a tangent. You need to be using 3/2 kT
http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/kintem.html
To calculate the translational kinetic energy of a molecule, you don't need to find the average speed or use the formula Ek = 1/2mv^2. Instead, you should use the formula Ek = 3/2kT, where Ek is the kinetic energy, k is Boltzmann's constant (approximately 1.38 x 10^-23 J/K), and T is the temperature in Kelvin.
Now, let's calculate the translational kinetic energy of O2 at the given temperatures:
a) At 300 K:
Ek = 3/2 * (1.38 x 10^-23 J/K) * 300 K
Ek ≈ 6.21 x 10^-21 J
b) At 1000 K:
Ek = 3/2 * (1.38 x 10^-23 J/K) * 1000 K
Ek ≈ 2.07 x 10^-20 J
As for the mass, you mentioned that it is not given in the problem. However, in this case, we are using the molar kinetic energy, which depends on the temperature and the gas constant. Therefore, you don't need the mass or the molar mass of O2.
Remember, when dealing with kinetic energy in gases, the formula Ek = 3/2kT is suitable for ideal gases or a large number of gas particles that can be treated statistically.