The sum of ...... energy and ...... energy of a system is called enthalpy of the system.

Explanation

To solve the question, we need to identify the two types of energy that, when summed together, give us the enthalpy of a system.

### Step-by-Step Solution:

1. **Understanding Enthalpy**: Enthalpy (H) is a thermodynamic property of a system that reflects the total heat content. It is defined as the sum of the internal energy of the system and the energy associated with the system's pressure and volume.

2. **Identifying Internal Energy**: The first type of energy we need to mention is **internal energy (E)**. Internal energy is the energy contained within the system due to the kinetic and potential energies of the molecules.

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