CHEMICAL REACTIONS TYPES OF REACTIONS There are five

CHEMICAL REACTIONS

TYPES OF REACTIONS • There are five types of chemical reactions we will talk about: 1. 2. 3. 4. 5. • Synthesis reactions Decomposition reactions Single displacement reactions Double displacement reactions Combustion reactions You need to be able to identify the type of reaction

1. SYNTHESIS REACTIONS • Synthesis reactions occur when two substances combine and form a compound. reactant + reactant 1 product • Basically: A + B AB • • Example: 2 H 2 + O 2 2 H 2 O Example: C + O 2 CO 2

2. DECOMPOSITION REACTIONS • • • Decomposition reactions occur when a compound breaks apart 1 Reactant Product + Product Basically: AB A + B Example: 2 H 2 O 2 H 2 + O 2 Example: 2 Mg. O 2 Mg + O 2

3. SINGLE REPLACEMENT REACTIONS • • • Single Replacement Reactions occur when one element replaces another in a compound. A metal can replace a metal (+) OR a nonmetal can replace a nonmetal (-). element + compound product + product A + BC AC + B (if A is a metal) OR A + BC BA + C (if A is a nonmetal)

SINGLE REPLACEMENT REACTIONS • Sodium chloride solid reacts with fluorine gas 2 Na. Cl + F 2 Na. F 2 + Cl 2 • Aluminum metal reacts with copper (II) nitrate 2 Al(NO 3)3 3 Cu+ 2 Al+3 Cu(NO 3)2

4. DOUBLE REPLACEMENT REACTIONS • • • Double Replacement Reactions occur when a metal replaces a metal in a compound a nonmetal replaces a nonmetal in a compound Compound + compound product + product AB + CD AD + CB

DOUBLE REPLACEMENT REACTIONS • Example: Ag. NO 3(aq) + Na. Cl(s) Ag. Cl(s) + Na. NO 3(aq) • Another example: 2 KNO 3(aq) + Ba. SO 4(s) K 2 SO 4(aq) + Ba(NO 3)2(aq)

5. COMBUSTION REACTIONS • • Combustion reactions occur when a substance reacts with oxygen gas. This is also called burning!!!

COMBUSTION REACTIONS • • • In general: Cx. Hy + O 2 CO 2 + H 2 O Products in combustion are ALWAYS carbon dioxide and water. Combustion is used to heat homes and run automobiles (octane, as in gasoline, is C 8 H 18)

COMBUSTION • Example • C 5 H 12 +8 O 2 5 CO 2 6+ H 2 O

MIXED PRACTICE • 1. 2. 3. 4. 5. State the type and balance the following reactions: Ba. Cl 2 + H 2 SO 4 Ba. SO 4 + HCl C 6 H 12 + O 2 CO 2 + H 2 O Zn + Cu. SO 4 Zn. SO 4 + Cu Cs + Br 2 Cs. Br Fe. CO 3 Fe. O + CO 2