Physical Versus Chemical Changes

Front 1

Is burning a match a chemical or physical change?

Back 1

Chemical change - gas released, color change, energy change with new substances created.

Front 2

Is breaking glass a chemical or physical change?

Back 2

Physical change - it is still glass with no change in the molecules.

Front 3

Is painting your nails a chemical or physical change?

Back 3

Physical - although there is a color change, it is not due to the creation of a new substance. It is only because the color of the polish is laid on top of the nail that it looks like a color change. When the polish is removed, the nail is still there with no change.

Front 4

Is melting icicles a chemical or physical change?

Back 4

Physical - the formula for water is H2O no matter whether it is a solid or a liquid. The molecules are just rearranged differently, but 2 hydrogen atoms are still bonded to 1 oxygen atom.

Front 5

Is cutting paper a chemical or physical change?

Back 5

Physical - no new substances are created. The paper is still paper, just in smaller pieces.

Front 6

Is the mixing of baking soda (sodium bicarbonate) and vinegar (acetic acid) a chemical or physical change?

Back 6

Chemical change - new substances are being created including a gas being released (carbon dioxide).

Front 7

Is the mixing of paint a chemical or physical change?

Back 7

Physical - the molecules in paint have not changed, they have just intermingled more. Believe it or not, the paint can be separated back into the colored pigments using a physical separation technique called chromatography.

Front 8

Is the digestion of an apple a chemical or physical change?

Back 8

Chemical - the molecules that make up that apple have been pulled apart and have formed new, simpler molecules. You definitely have a color change, gas released, and energy change during digestion!

Front 9

Is grass growing a chemical or physical change?

Back 9

Chemical - photosynthesis causes the molecules in the grass to take in carbon dioxide and water, and using light energy, created oxygen and glucose...new molecules. The grass is not stretching, it is becoming longer and larger due to more molecules.

Front 10

Is metal rusting a chemical or physical change?

Back 10

Chemical - new molecules are formed with a new color to them. This particular chemical change is considered irreversible, unfortunately.