9.672m/s
The most probable speed of a molecule at a given temperature is:
Vmp=sqrt(2*R*T/M)
where R is the gas constant, T is the absolute temperature, and M is the molar mass of the gas.
R is 8.314J/(mol*K)
T is given as 270K
Molar mass must be calculated using the fact that Ozone has 3 oxygen atoms and oxygen has an atomic mass of 15.999.
15.999*3 = 47.997
Plugging this in to the formula gives:
sqrt(2*8.314*270/47.997) = sqrt(4489.56/47.997) = 9.672m/s
