Basic Chemistry

Matter - Anything that has mass and takes up space *everything we see, touch, taste or smell

ATOMS-all matter is made up of these small, indivisible particles.  Atoms have a nucleus (center)made of protons and neutrons  protons are positively charged particles  neutrons are particles with no charge  electrons-tiny negatively charged particles that orbit (circle) the nucleus

Atoms have equal numbers of electrons (-) and protons (+) so they are neutral. ATOMIC NUMBER: number of protons in the nucleus of an atom *this identifies an atom Ex. See atomic # ATOMIC MASS: the sum of protons and neutrons of an atom Atomic #= Protons = Electrons Atomic mass= Protons + neutrons

A chemical element is a pure substance that consists of one type of atom. Elements represented by symbols: C for Carbon

Isotopes: atoms of an element that have different number of neutrons, but same number of protons.

Chemical compound: substance formed by combinations of 2 or more elements (atoms) in definite proportions. Compounds represented by Chemical formulas Ex. H 2 SO 4

Ionic bonds: one or more electrons are transferred to another atom Ex. NaCl

Covalent bonds: when electrons are shared between atoms Ex. H 2 O

Van der Waals Forces: molecules close together have slight attraction (not that strong) Ex. Gecko lizards ability to climb walls.

4 groups of organic compounds found in living things: 1. Carbohydrates: Living things use carbs as main source of energy.  Sugar and starch molecules  made of H and O  animals- use in liver and muscles  plants-for food and cellulose

2. Lipids: can be used to store energy. Makes biological membranes of cells and waterproof coverings.  fats, oils, waxes  made of C and H atoms Cell Membrane

3. Nucleic Acids: store and transmit hereditary information  2 kinds (RNA, DNA)  made of H,O,N,C,P atoms RNA strand

4. Proteins: control rate of reactions, regulate cell processes, form bone and muscles, transport substances in/out of cells or fight disease.  made of C,H,O atoms  made of amino acids (compounds) Protein: made of amino acid chains folded up Amino Acid Chain