Chapter 2 chemistry of Life

Atoms *Atom is the fundamental unit of matter. *Can only be seen with an electron microscope. *Backed by research, fact, and experimentation.

Parts of the atom include Nucleus- has two sub atomic particles -Proton and neutron -Proton has a positive charge -Neutron has no electrical charge Electrons circle the nucleus and have a negative charge

Elements- these are substances that cannot be broken down chemically into simpler substances.

CHNOPS Elements 92 naturally occurring elements Only six are abundant in living things Carbon Hydrogen Nitrogen Oxygen Phosphorus Sulfur CHNOPS

Isotopes- an atom of an element that has a different number of neutrons than other atoms of that element *most elements have two or more isotopes The average mass of all of an elements isotopes is the atomic mass of the element which is listed on the periodic table

Radioisotopes- radioactive isotopes that release radiation that is valuable in experimentation.

Compounds- consist of atoms of two or more elements Example: Water contains two Hydrogen molecules and one Oxygen molecule

Compounds- consist of atoms of two or more elements Example: Water contains two Hydrogen molecules and one Oxygen molecule H2O two gas elements combine to form a liquid.

Compounds- consist of atoms of two or more elements Example: Water contains two Hydrogen molecules and one Oxygen molecule H2O two gas elements combine to form a liquid. NaCl two deadly elements combine to form table salt.

Ionic Bonds- A bond formed by the electrical attraction between two oppositely charged ions. -one positive and one negatively charged ion -one electron is given from one atom to the other atom ion- an atom with an electrical charge -This is cause when an electron is either given away or received from another atom. Example: NaCl

Covalent Bonds- Forms when two atoms share one or more pairs of electrons. Example: Water

Why is this important in Biology?

The BIG picture. Why do we study atomic structure in Biology?