(275) Chemical Change

Chemical Change

A process that results in the formation of a new substance through the breaking and forming of bonds.

Physical Change

A change that alters the form of a substance but does not change its chemical identity.

Cellular Respiration

A series of chemical reactions in which food and oxygen are converted into carbon dioxide and water, resulting in mass loss.

Macroscopic Level

The large-scale observation of changes that can be seen without the aid of a microscope.

Evidence of Chemical Change

Indicators such as changes in odor, color, gas production, heat change, or formation of a precipitate.

Evidence of Physical Change

Primarily a change in the state of matter (solid, liquid, gas) without altering the substance's chemical identity.

Rotting Fruit

An example of a chemical change characterized by gas production and color change, difficult to reverse.

Rusting Iron

A chemical change involving a color change and heat production, also hard to reverse.

Crushing Aspirin

A physical change as there is no change in chemical identity or production of gas.

Burning Paper

A chemical change due to the combination with oxygen and irreversible nature.

Boiling Water

A physical change as it involves a change in state without altering the chemical identity.

Dissolving Sugar

A physical change where sugar molecules are separated but remain chemically unchanged.

Melting Butter

A physical change where the substance changes from solid to liquid but remains butter.

Acid-Base Changes

A type of chemical change observable through color changes in indicators like cabbage juice.

Formation of Precipitate

An indication of a chemical change where a solid forms from a solution.

Redox Reaction

A chemical change involving the transfer of electrons, often observable in titrations.

Titration

A laboratory method used to determine the concentration of a substance, often involving color changes.