ENERGY &

ENERGY &CHEMICAL REACTIONS

Energy- The ability to do work

States of Matter - videoSolids maintain a fixed volume and shape. molecules move less rapidly than liquids or gasesLiquids maintain a fixed volume, but its particles move more freely than a solid ability to flow and conform to the shape of any container Gases are composed of particles that move the most. They occupy the space available to them Thermal energy must be added or removed for a substance to change states of matter

Chemical Reaction - videowhen one or more substances change to produce one or more different substancesEnergy is absorbed or released when chemical bonds are broken or new ones are formedThe following is an example of a chemical reaction CO2 + H2O H2CO3CO2 and H2O are reactants (found on tail side of the arrow)H2CO3 is the product( found on the head of the arrow)

There are thousands of chemical reactions that occur inside the human bodyReactions that break down food we eat for energy Reactions that build muscleReactions that regulate the amount of sugar in our blood

Oxidation Reduction ReactionsReactions in which electrons are transferred between atomsalso known as redox reactions Oxidation reactions a reactant loses one or more electrons, thus becoming more positiveReduction reactions- a reactant gains one or more electrons, thus becoming more negative

Activation energy - videothe amount of energy needed to start a chemical reactionCatalysts speed up the rate of the reaction by lowering the amount of activation energy needed to start the reactionIn living things enzymes act as catalysts. An enzyme is a protein or RNA molecule that speeds up a metabolic reaction without being permanently changed or destroyed

ENZYMESEach type of enzyme catalyzes only ONE or a few specific reactionsHave an Active Site: region of enzyme that binds to the substrategroove on proteins surface that determines specificitychanges its shape in response to the substrate

Substrate: The substance an enzyme acts on and makes more reactive

Factors that affect Enzyme ActivityEnzyme concentrationSubstrate concentrationTemperatureCompetitive inhibitorspH