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 particlesneutrons 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 atomEx. See atomic #

ATOMIC MASS: the sum of protons and neutrons of an atom

Atomic #= Protons = ElectronsAtomic 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. H2SO4

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

Ex. NaCl

Covalent bonds: when electrons are shared between atoms

Ex. H2O

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