Answer:
V = 20.6 m/s
Explanation:
Given that the temperature of the neon molecules = 356 Kelvin
Pressure = 0.9 bar
The mass number of Neon = 21.
Using the formula below
1/2 m v^2 = (3kT)/2
Where
T = temperature = 356 k
K = Bolzmann constant
= 1.38 × 10^-23jk^-1
NA = 6.02214076×10²³ mol⁻¹
Where NA = Avogadro number
Substitute all the parameters Into the formula
1/2 × 21/NA × v^2 = (3 × k × 356)/2
1.744×10^-23V^2 = 7.3692 × 10^-21
Make V^2 the subject of formula
V^2 = (7.37×10^-21)/1.744×10^-23
V^2 = 422.55
V = sqrt( 422.55)
V = 20.55
Therefore, the average (root mean square) velocity (m/s) of Neon molecules at 356 Kelvins and 0.9 bars is 20.55 m/s