Would the energy of a phase change (let's say going from a gas to a liquid) be equal to the energy of all newly formed intermolecular bonds being formed as the gas transitions to liquid?

Would the energy of a phase change (let's say going from a gas to a liquid) be equal to the energy of all newly formed intermolecular bonds being formed as the gas transitions to liquid?

 

The energy needed to vaporize a substance is the same amount of energy given off when that energy condenses. Condensation is actually and exothermic process as the motion of particles decrease thus decreasing their kinetic energy.

Intermolecular forces are usually negligible in the gas phase, but at high temeratures, pressures and mico-volumes, the behaviour of gases deviates significantly from the ideal gas equation.

To answer your question: No, not exactly, but the enthalpy of vapoization (given by the Clausius-Clapeyron equation) accounts for the overcoming of van-der Waals, and or hydrogen-bonding interactions depending on the specific liquid. Look up Born-Haber Cycles in chemical thermodynamics