Explain how boiling and evaporating are alike and how they are differant

The main difference between evaporation and boiling are : 1. Evaporation takes place at all temperatures, while boiling occurs at a particular temperature. 2. Evaporation takes place from the surface, whereas the entire liquid boils. 3. Evaporation can occur using the internal energy of the system, while boiling requires an external source of heat.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

i think its 100

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