Atoms are __________________________ (NOT created or destroyed) Chemical Reactions CHEMICAL REACTIONS Occur when substances undergo chemical changes to form _______________________________. Atoms are __________________________ (NOT created or destroyed) Parts of a Reaction ____________________________ Substance or molecule that participates in a chemical reaction. On ___________________ side of arrow in chemical equation Substance that forms in a chemical reaction. 2H2 + O2  2H2O (Reactants) (Products)

CHEMICAL BONDS BETWEEN ATOMS (Ionic and Covalent) Chemical Reactions CHEMICAL BONDS BETWEEN ATOMS (Ionic and Covalent) Sometimes energy must be ___________ to ______________ bonds. ____________________________________= energy required to begin or finish a reaction Many forms of energy can be used to break bonds such as heat, light, electricity, and sound. Often forming bonds __________________________ energy (like explosions).

CONSERVATION OF ENERGY AND MASS Chemical Reactions CONSERVATION OF ENERGY AND MASS Mass and energy are ______________________ in chemical reactions. The total energy and mass that exists before the reaction is equal to the total energy and mass of the products and their surroundings. HEAT AND CHEMICAL REACTIONS ________________________ reaction = chemical reaction in which heat is released to the surroundings. ________________________ reaction = chemical reaction that absorbs heat.

Chemical Reactions SPEED OF A REACTION __________________________ = substance that changes the ______________________________ _____________________________ without being consumed or changed significantly. Catalysts are _____________ reactants or products, because they are not used up in the reaction. Catalysts are often used in industry to make reactions go faster. Catalysts in your body are called __________________________

____________________ Reaction Chemical Reactions ____________________ Reaction Two or more substances _____________________ to form a new compound. Synthesis reactions have the following general form: A + B AB Example: 2Na + Cl22  2NaCl ____________________ Reaction A single compound _____________________ to form two or more simpler substances. Decomposition reactions have the following general form: AB  A + B Example: 2H2O  2H2 + O2

# 3 Reaction #4 Reaction Chemical Reactions _______________________ _______________________ Reaction ____________ element or ion _________________________ of another element or ion in the compound. Single-displacement reactions have the following general form: AX + B  BX + A Example: 3CuCl2 + 2Al  2AlCl3 + 3Cu ________________________ ________________________ Reaction A gas, a solid precipitate, or a molecular compound forms from the apparent __________________________ __________________________ between _______ compounds. Double-displacement reactions have the following general form: AX + BY  AY + BX Example: Pb(NO3)2 + K2CrO4  PbCrO4 + 2KNO3

_______________________ Reaction Chemical Reactions _______________________ Reaction The reaction of a carbon-containing compound, in which _______________________________. Combustion reactions use O2 as a reactant. H2O and CO2 is a common product of combustion reactions. Example: CH4 + O2  CO2 + 2H2O + heat