A chemist while studying the properties of gaseous `C_(2)Cl_(2)F_(2)`, a chlorofluoro carbon refrigerant, cooled a `1.25 g` sample at constant atmospheric pressure of `1.0 atm` from `320 K` to `290 K`. During cooling, the sample volume decreased from `274` to `248 mL`. Calculate `Delta H` and `Delta U` for the chlorofluoro carbon for this process. For `C_(2)Cl_(2)F_(2)`, `C_(P) = 80.7 J mol^(-1) K^(-1)`.

Explanation

To solve the problem, we need to calculate the change in enthalpy (ΔH) and the change in internal energy (ΔU) for the chlorofluorocarbon refrigerant \( C_2Cl_2F_2 \) during the cooling process.

### Step 1: Calculate the number of moles of \( C_2Cl_2F_2 \)

Given:
- Mass of \( C_2Cl_2F_2 \) = 1.25 g
- Molar mass of \( C_2Cl_2F_2 \):
- Carbon (C) = 12 g/mol, so \( 2 \times 12 = 24 \) g/mol
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