The Titel

The Titel

Patrick Killen
September 13, 2008
Period 1 Biology

Section 6.1 Atoms and Their Interactions


Main Idea

* Atoms are the basic building blocks of all matter.

* Atoms consist of a nucleus containing protons and neutrons. The positively charged nucleus is surrounded by a cloud of rapidly moving, negatively charged electrons.

* Atoms become stable by bonding to other atoms through covalent or ionic bonds.

* Components of mixtures retain their properties—components of solutions do not

Acid: Any substance that forms hydrogen ions (H+) in water and has a pH below7.

Atom: Smallest particle of an element that has the characteristics of that element; basic building block of all matter.

Base: Any substance that forms hydroxide ions (OH-) in water and has a pH above 7.

Compound: Substance composed of atoms of two or more different elements that are chemically combined.

Covalent Bond: Chemical bond formed when two atoms combine by sharing electrons.

Element: Substance that can’t be broken down into simpler chemical substances.

Ion: Atom or group of atoms that gain or lose electrons; has a positive or negative charge.

Ionic Bond: Chemical bond formed by the attractive forced between two ions of opposite charge.

Isotope: Atoms of the same element that have different numbers of neutrons in the nucleus.

Metabolism: All of the chemical reactions that occur within an organism.

Mixture: Combination of substances in which individual components do not combine chemically and retain their own properties.

Molecule: Group of atoms held together by a covalent bonds; has no overall charge.

Nucleus: Positively charged center of an atom composed of neutrons and positively charged protons, and surrounded by a cloud of negatively charged electrons; in eukaryotic cells the central membrane-bound organelle that manages cellular functions and contains DNA.

pH: Measure of how acidic or basic a solution...