Answer:
The average translational kinetic energy per atom for nitrogen atoms (not N₂) in a gas of nitrogen at atmospheric pressure at a temperature of 81 ∘C = 7.32 × 10⁻²¹ J
Step-by-step explanation:
Average translational kinetic energy is given by
Eₐᵥ₉ = 3RT/2Nₐ
R = molar gas constant
T = absolute temperature in Kelvin
Nₐ = Avogadro's constant
The average translational kinetic energy is given more conveniently as
Eₐᵥ₉ = 3kT/2
k = Boltzmann's constant = (R/Nₐ) = 1.381 × 10⁻²³ J/K
T = 81 + 273.15 = 353.15 K
Eₐᵥ₉ = (3 × 1.381 × 10⁻²³ × 353.15)/2 = 7.32 × 10⁻²¹ J