Chemical Reactions Study Guide 1. The Law of Conservation: no matter can be created or destroyed. This Law explains that the mass (makeup) of the reactants must be equal to the mass (makeup) of the product for the equation to be balanced. 2. They tell you how many of one molecule is needed to react with another. In other words they give the ratio that the molecules combine in. 3. The reactants are to the left of the arrow in the equation and the products are to the right of the arrow. Reactants Products 4. Chemical equations need to be balanced in order to satisfy the law of conservation of matter, which states that in a closed system matter is neither created nor destroyed. 5. A + B AB A synthesis reaction is a type of reaction in which multiple reactants combine to form a single product. 6. AB A + B A decomposition reaction is a type of chemical reaction in which a single compound breaks down into two or more elements or new compounds. 7. A + BC AC + B A single displacement reaction is when one element replaces another in a compound. (a metal replaces meta and a nonmetal replaces nonmetal) 8. AB + CD AD + CB A double displacement reaction is when the ions in the two compounds exchange bonding partners, usually written in the form. 9. Exothermic Reaction: reaction that releases energy (feels hot). Energy released by making new bonds outweighs energy required to break old bonds. 10. Endothermic Reaction: reaction that absorbs energy (feels cold). Energy required to break old bonds outweighs energy released by making new bonds. 11.

Double Displacement 12. Double Displacement/ Synthesis 13. Single Displacement 14. Single Displacement 15. Decomposition 16. Single Displacement 17.

Synthesis 18. Synthesis 19. (aq) aqueous is a solution
(s) solid