Oliver Thomas
Atoms
 Unable to be cut
 Basic unit of matter
 Made of protons, neutrons, and electrons
 Protons are positive
 Neutrons carry no charge
 Electrons are negative
Elements and Isotopes
 More then 100
 Represented by one or two letter symbols
 Different numbers of neutrons
 Identified by their mass numbers
 Some are radioactive
 Can be dangours
Chemical Compounds
 Formed by two or more in definite proportions
Chemical Bonds
 Main types are ionic bonds and covalent bonds
 Ionic Bon- The are created by one or more are
transferred from one atom to another
 Covalent bonds-Created when electrons are shared
between atoms
The Water Molecule
 Like molecules, water molecules are neutral.
 A water molecule is polar because there is an uneven
distribution of electrons between the oxygen and
hydrogen atoms.
Solutions and Suspensions
 Water is not always pure-it is often found as part of a
mixture.
 A mixture is a material composed of two or more
elements or compounds that are physically mixed
together but not chemically combined.
The Chemistry of Carbon
 Carbon atoms have four valence electrons.
 Each electron can join with an electron from another
atom to form a strong covalent bond.
 Carbon can bond with many elements, including
hydrogen, oxygen, phosphorus, sulfur, and nitrogen.
Macromolecules
 Macromolecules are made from thousands or even
hundreds of thousands of smaller molecules
 The smaller units, or monomers, join together to form
polymers.
 Four groups of organic compounds found in living
things are carbohydrates, lipids, nucleic acids, and
proteins
Carbohydrates
 Carbohydrates are compounds made up of carbon,
hydrogen, and oxygen atoms.
 Living things use carbohydrates as their main source
of energy.
 Plants and some animals also use carbohydrates for
structural purposes.
Lipids
 Lipids are made mostly from carbon and hydrogen
atoms.
 Lipids can be used to store energy.
 Some lipids are important parts of biological
membranes and waterproof cover
Nucleic acids
 Nucleic acids are macromolecules containing
hydrogen, oxygen, nitrogen, carbon, and phosphorus.
 Nucleic acids store and transmit hereditary, or genetic,
information.
 There are two kinds of nucleic acids- Ribonucleic acid,
and deoxyribonnucleic
Proteins
 Proteins are macromolecules that contain nitrogen as
well as carbon, hydrogen, and oxygen.
 Proteins are polymers of molecules called amino acids.
Chemical Reactions
 Chemical reaction is a process that changes one set of
chemicals into another set of chemicals.
 Chemical reactions always involve the breaking of
bonds in reactants and the formation of new bonds in
products
Energy In Reactions
 Chemical reactions that release energy often occur
spontaneously.
 Chemical reactions that absorb energy will not occur
without a source of energy.
Enzymes
 Cells use enzymes to speed up chemical reactions that
place in cells.
 Enzymes are very specific, generally catalyzing only
one chemical reaction
Enzymes Action
Enzymes provide a site where reactants can be brought
together to react.