2. 5 categories of chem. rxn. 1. Synthesis 2. Decomposition 3. Single replacement 4. Double replacement 5. Combustion

3. 1. Synthesis Two or more substances put together A + B  AB General

4. Specific Example 2Na + Cl 2  2NaCl

5. 2. Decomposition Compound breaks down into 2 (or more) substances AB  A + B General

6. Specific Example H 2 O 2  H 2 O + O 2 22 Hydrogen peroxide decomposes into water & oxygen gas

7. 3. Single-replacement One element replaces another in a compound AB + C  CB + A General

8. MgCl 2 + 2 Li  2LiCl + Mg Li takes place of Mg 3CuSO 4 +2Al  Al 2 (SO 4 ) 3 + 3Cu Al takes the place of Cu Specific Example

9. 4. Double replacement The positive portions ( + ions) are exchanged General AX + BY  AY + BX

10. Specific Example AgNO 3 +NaBr  AgBr +NaNO 3 Ag + & Na + exchange places

11. 5. Combustion Substance combines w/ oxygen rapidly - forms one or more oxides Substance A + O 2 Substance oxide + energy releases energy

12. Specific Example 2 C 2 H 2 + 5 O 2  4 CO 2 + 2 H 2 O + energy Acteylene combines w/ oxygen & produces carbon dioxide & water & releases energy http://exploscience. com/explosciencew ebsite2/ChemTV_P age_5.htmlexploscience. com/explosciencew ebsite2/ChemTV_P age_5.html