Elements, Compounds, and Mixtures

Covalent

A chemical bond between two non-metal atoms where pairs of electrons are shared between the non-metal atoms.

Compound

A substance made up of atoms of two or more different elements joined by chemical bonds.

Heterogeneous Mixture

Any combination of substances that does not have uniform composition and properties; a mixture of physically distinct substances with different properties.

The smallest identifiable unit of an element is a(n) _________.

Atoms

In a mixture, the substances involved (can/ cannot) be seperated by a simple physical process. In a compound, the elements involved (can/ cannot) be spereated by a simple physical process because the elements are (physically combined/ chemically bonded).

Can; Cannot; Chemically bonded

Homogeneous Mixture

A mixture in which substances are evenly distributed throughout the mixture.

Element

A pure substance that cannot be broken down into other substances by chemical or physical means.

Pure Substance

A sample of matter, either a single element or a single compound, that has definite chemical and physical properties.

Mixture

A substance consisting of two or more substances mixed together (not in fixed proportions and not with chemical bonding).

silver, chromium, hydrogen, carbon, nitrogen, oxygen, gold, sulfur, magnesium, nickle

Elements

Monoatomic

Exist in nature as single atoms - uncombined with other elements (e.g., Ag, Pt, Au, He, Ne)

True/ False A mixture is always made up of a combination of elements.

False

True/ False: An element can be broken down into a simpler substance

False

In a mixture, the substances (lose/ retain) their identities.

Retain

Ionic

a chemical bond in which a METAL atom loses an electron to form a positive cation and a NONMETAL atom gains an electron to form a negative anion

In a compound the (atoms/molecules) are (chemically/physically) combined so that the elements that make up the compound (retain/lose) their identities and (do/do not) take on a new set of properties.

atoms; chemically; lose; do

The smallest identifiable unit of a compound is a(n) ___________, which is made up of ____________ which are chemically bonded.

element; atoms

A mixture (is/is not) a chemical combining of substances.

is not

Polyatomic

positively or negatively charged, covalently bonded group of atoms. Consisting of many atoms.