While paraffin wax is melting, is the net flow of thermal energy from the
wax to the surroundings OR from the surroundings to the wax? *

To melt solid paraffin wax, one would need to add thermal energy to the system of solid paraffin wax.

This means the direction of flow of thermal energy to melt the paraffin wax is from the surroundings to the wax.

Explanation:

Melting entails the the change of phase of a substance from solid phase to liquid phase at a constant temperature as a result of added thermal energy.

As it is evident, moving from a more organised phase of matter to another phase with more overall average energy will require energ input.

So, to liberate the molecules of solid paraffin wax and turn the paraffin wax from solid phase to a more mobile liquid phase, in melting, one would need to add thermal energy to the paraffin wax in solid state.

Hope this Helps!!!

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