52. Solving a chemistry problem

52. Solving a chemistry problem

An ideal gas, helium, at a temperature of 700 K, occupies a volume of 41 liters. At a constant pressure of 1 atm, it was transferred to a state with a temperature of 400 K.
Need to find:
1) number of moles of gas;
2) the change in entropy during this transition, assuming that the heat capacity of the gas does not depend on temperature

Additional information:

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