BASIC CHEMISTRY

WHAT IS MATTER? Anything that takes up space Mass is equal to the amount of matter in an object and is constant regardless of gravity

STATES OF MATTER What are the 3 states? Solid, Liquid, Gas

ENERGY Capacity to do work Kinetic-Motion Potential-Stored

WHAT ARE SOME FORMS OF ENERGY? Chemical- Stored in Bonds Electrical-Movement of charged particles Mechanical-Involved with moving matter Radiant-Energy in waves

COMPOSITION OF MATTER Elements are unique substances that cannot be broken down into simpler substances by ordinary chemical means Four elements-Carbon, Hydrogen, Nitrogen and Oxygen make up 96% of our body weight Atoms are smallest particles of an element Elements are designated a one or two letter abbreviation called the atomic symbol

ATOMIC STRUCTURE Each atom has a nucleus with tightly packed Protons and Neutrons Protons=Positive charge and weigh 1 atomic mass unit (amu) Neutrons=No Charge and weigh 1 amu Electrons-Negative Charge and move around the nucleus and are weightless (0 amu) Atoms are neutral in charge and number of electrons = number of protons

IDENTIFYING ELEMENTS Elements are identified based on number of protons, neutrons and electrons Atomic # is EQUAL to Number of PROTONS Mass # of an element is equal to number of protons PLUS number of neutrons

ISOTOPES Structural Variations of an atom that have same number of Protons but differ in number of Neutrons Atomic weight is an average of all the relative weights of all known isotopes of and element

CHEMICAL BONDS

1.WHAT ARE THE ROLE OF ELECTRONS IN CHEMICAL BONDING? Electrons occupy space called electron shells Each shell represents a different energy level Each Electron Shell holds a specific number of electrons Octet Rule (Rule of 8’s) Atoms are stable with 8 electrons in their valence shell

CHEMICAL BOND TYPES Ionic-Transfer one electron from one atom to another Ions-charged particles Anions-electron acceptor carrying a net negative charge Cation- electron donor carrying a net positive charge

COVALENT BONDS Shared Electrons Can result in double or triple bonds with sharing Nonpolar share electrons evenly between two atoms Polar-partial neg charge for one atom the other has a partial pos charge

HYDROGEN BONDS Weak attractions in polar molecules Water molecules

CHEMICAL REACTION Occur whenever bonds are formed, rearranged or broken Chemical equations describe what happens in a reaction Balanced

CHEMICAL REACTION PATTERNS Synthesis-Combination Decomposition- Broken DOWN Exchange-( Displacement) involve both Synthesis and Decomposition Oxidation-Reduction= Special exchange reaction

ENERGY FLOW Exergonic-Release energy as product Endergonic- Absorb energy

FACTORS THAT INFLUENCE THE RATE OF CHEMICAL REACTIONS Chemicals react when they collide with enough force to overcome the repulsion of their electrons Increase in temperature Smaller particles= faster rate of reaction Higher concentration of particles= faster rate of reaction Catalysts increase the rate of a chemical reaction without taking part in the reaction