Question

What else beside molecular kinetic energy contributes to the internal energy of a substance?

Answer 1

•The internal energy can be changed by changing the temperature or volume of the object without changing the amount of particles in the object.

•Temperature: If the temperature of a system rises, the molecules will travel quicker, therefore have more kinetic energy and so the Internal Energy will increase.

•Pressure: If the pressure falls but the temp doesn’t change then there is no change in the internal energy of a system. In a non-ideal expanding gas the molecules have to overcome the attraction to each other and therefore some work must be done on them and therefore the internal energy must increase.

•State: For most materials that change from solid to liquid the volume increases and so the potential energy of the molecules increases.

Answer 2

Forms of Energy
Law of Conservation of Energy
Energy Efficiency
Sources of Energy
What is energy?
Energy makes change; it does things for us. It moves cars along the road and
boats over the water. It bakes a cake in the oven and keeps ice frozen in the
freezer. It plays our favorite songs on the radio and lights our homes. Energy
makes our bodies grow and allows our minds to think. Scientists define energy as
the ability to do work. People have learned how to change energy from one form
to another so that we can do work more easily and live more comfortably.
Forms of Energy
Energy is found in different forms, such as light, heat, sound and motion. There
are many forms of energy, but they can all be put into two categories: kinetic and
potential.
KINETIC ENERGY
Kinetic energy is motion––of waves,
electrons, atoms, molecules, substances,
and objects.
POTENTIAL ENERGY
Potential energy is stored energy and the
energy of position––gravitational energy.
There are several forms of potential energy.
Electrical Energy is the
movement of electrical
charges. Everything is
made of tiny particles
called atoms. Atoms are
made of even smaller
particles called electrons,
protons, and neutrons.
Applying a force can make
some of the electrons
move. Electrical charges
moving through a wire is
called electricity.
Lightning is another
example of electrical
Chemical Energy is energy
stored in the bonds of atoms
and molecules. It is the
energy that holds these
particles together. Biomass,
petroleum, natural gas, and
propane are examples of
stored chemical energy.
Stored Mechanical
Energy is energy stored in
objects by the application of a
force. Compressed springs
and stretched rubber bands
are examples of stored