[CHEM] Classification of Matter, Measurements, Scientific Notations, and Significant Figures

Chemical properties

Characteristics that describe how matter changes its chemical structure or composition

Element

A substance that cannot be broken down into chemically simpler components

Compound

A substance that can be broken down into chemically simpler components (because it consists of more than one element)

Atom

• Smallest part of an element

• Maintains its identity

Substance

Any sample of matter that has the same physical and chemical properties throughout the sample

Molecule

• The smallest part of a compound that maintains the identity of the said compound.

• Composed of two or more atoms that are attached together and behave as a unit

Mixture

• A material composed of two or more substances.

• In a mixture, the individual substances maintain their chemical identities.

Heterogenous mixtures

• Obvious combinations of two or more substances

  • E.g.: sand and water

Homogenous mixture

• also known as solutions

• Mixtures with a consistent or uniform composition throughout

• intimately combined components that act like a single substance (but they aren’t)