Why is heat not considered matter?

Answer 1

Matter has mass and occupies volume. Heat, light, and other forms of electromagnetic energy do not have measurable mass and can't be contained in a volume. Matter can be converted into energy, and vice versa.

Answer 2

In a practical sense, heat does not have mass as we normally experience mass. We normally reserve the term matter something with mass.

If you have an object that is hot and an identical object that is cold, a normal scale would not measure a difference in mass or weight.

(If you tried to do such a measurement, it would be complicated by the fact that normally objects are weighed in air and air currents are created by heating or cooling and so would introduce a small source of error.)

There is one caveat that arises when we incorporate the theory of relativity.

To be very technical, heat does have mass because heat is a form of energy and mass and energy are related by Einstein's famous equation, E=mc^2.

So, technically, as an object is heated, the molecules move faster and have more kinetic energy. (Potential energy can come into play as well.) More energy means more mass. For any object in normal human experience and normal temperatures, the change in mass is tiny tiny tiny and far too small to measure. On an astronomical scale, at temperatures such as those generated in a star, the mass change would be larger but other complications and the presence of electromagnetic or nuclear energy make the discussion more complicated.

So, strictly speaking, it would be correct to say that heat energy does increase the mass of an object by an amount given by Einstein's equation primarily because the constituent atoms of the object have an increased mass.

Answer 3

What i understand is that there is noting call "Light" or "Heat" its just the "Space",. "Space" created between sub atomic particles and atom we understand and call it "Light" and our eye recognizes it - and "Space" created between atom, molecules and cells we feel it and call it "Heat" - our cells / skin feels it

IF "Light" is a "particle" or "wave" then you should not see the same star from just one feet away -

your eye should loose the particle as it should have gained a little space during its million kilometer journey.

Rajeev. Colombo.

OLD reply >>

Light (including all forms of electromagnetic radiation) is not considered matter because it has no rest mass. Heat doesn't have rest mass either, in fact it is nothing other than the random motion of atoms. These things have energy. They interact with other stuff. But they aren't matter because they aren't what material objects are made up of.

Alternatively: Light and heat are not tangible things that you can see, touch or weight. One can not chemically isolate atoms of heat or light.

There is no official answer to this question because everyone just takes is as a given fact.

Answer 4

Heat is not considered a form of energy because it falls under the bracket of kinetic energy. Effectively, a hot subtance has particles that are moving much quicker and vibrating a lot more than they would when they were cooler. When you touch this substance the now quicker particles collide with your skin much more frequently than they usually would and so you feel heat/pain.

Hope this helps.

Answer 5

because Matter has mass and occupies volume. Heat, light, and other forms of electromagnetic energy do not have measurable mass and can't be contained in a volume. Matter can be converted into energy, and vice versa.

Answer 6

nope. Solids, Gasses, and Liquids are considered matter.

Answer 7

Heat is not composed of atoms, therefore it is not matter, it is energy.

Answer 8

it is a type of energy

Answer 9

They do not contain elements.