Question

Why do molecules and atoms speed up when the amount of heat added increases?

Answer 1

Answer:

As heat energy is added to a substance, its molecules speed up. Since molecules are always in motion, their movement is described as vibrating in place.

Answer 2

Explanation:

Summary. Heat is the energy an object has because of the movement of its atoms and molecules which are continuously jiggling and moving around, hitting each other and other objects. When we add energy to an object, its atoms and molecules move faster increasing its energy of motion or heat.