3/26/12 - Bellringers What is happening in this chemical reaction? Turn in bellringers if absent Friday!

23.3 – Classifying Chemical Reactions

Combustion Reaction Type of synthesis reaction that produces heat and light –Involves a carbon compound plus oxygen gas to produce carbon dioxide and water EX - 2 C 2 H O 2  4 CO H 2 O Also fits into other reaction types

Synthesis Reaction Two or more substances form a new substance A + B  C Example – hydrogen burning in oxygen to become water

Decomposition reaction One substance breaks down into two or more substances AB  A + B Most require the use of heat, light, or electricity

Single-Displacement Reaction One element replaces another one in a compound A + BC  AC + B D + BC  BD + C

Activity Series In single displacement reactions, more reactive metals can replace less reactive metals Most reactive – lithium, potassium, sodium Least reactive – gold, silver, copper

Double-Displacement Reaction Results if a precipitate, water, or a gas forms when two ionic compounds in solution are combined Precipitate – insoluble compound that comes out of a solution in a DD reaction AB + CD  AD + CB

Synthesis A + B  AB Na + Cl 2  NaCl Decomposition AB  A + B 2NaCl  2Na + Cl 2 Single-Displacement A + BX  AX + B Mg + CuSO 4  Cu + MgSO 4 Double-displacement AX + BY  AY + BX CaCO 3 + HCl  CaCl 2 + H 2 CO 3

Video HHvx1VC_8http:// HHvx1VC_8

In class assignment/homework… 23.3 Reinforcement WKT