# What is the rate of thermal motion of molecules if, when moving 250 kPa, a gas weighing 8 kg

October 8, 2021 | education

| **What is the rate of thermal motion of molecules if, when moving 250 kPa, a gas weighing 8 kg occupies a volume of 15 m3?**

To find out the required speed of thermal motion, we use the formula: V = √ (3P / ρ) = √ (3P * V / m).

Data: P – pressure (P = 250 kPa = 25 * 10 ^ 4 Pa); V is the volume occupied by the gas (V = 15 m3); m is the mass of the gas (m = 8 kg).

Let’s make a calculation: V = √ (3P * V / m) = √ (3 * 25 * 10 ^ 4 * 15/8) ≈ 1185.85 m / s.

Check: [m / s] = √ (Pa * m3 / kg) = √ (kg / (m * s2) * m3 / kg) = √ (m2 / s2) = m / s (correct).

Answer: The speed of thermal movement, according to the calculation, is 1185.85 m / s.