A vessel of capacity 0.30 `m^(3)` contains 3.00 mol of helium gas at `20^(@)C`. (i) Find the total thermal energy of the system. (ii) Find the average kinetic energy per molecule.

Explanation

To solve the problem step by step, we will first find the total thermal energy of the helium gas in the vessel and then calculate the average kinetic energy per molecule.

### Given Data:
- Volume of the vessel, \( V = 0.30 \, m^3 \)
- Number of moles of helium gas, \( n = 3.00 \, \text{mol} \)
- Temperature, \( T = 20^\circ C = 20 + 273 = 293 \, K \)

### (i) Total Thermal Energy of the System
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