1. TYPES OF CHEMICAL REACTIONS, CONTINUED

2. AB + CD AD + CB DOUBLE REPLACEMENT Ions in two compounds change partners Cation of one compound combines with anion of the other General Equation:

3. DOUBLE REPLACEMENT PRODUCTS One of the compounds formed is usually either: The other compound is often soluble and remains dissolved in solution. A precipitate An insoluble gas that bubbles out of solution Or, a molecular compound, usually water

4. DOUBLE REPLACEMENT EXAMPLE Pb(NO 3 ) 2 (aq) + K 2 CrO 4 (aq) PbCrO 4 (s) + 2KNO 3 (aq) Note how the ions combine to create neutral products by crossing charges and simplifying. Then…the equation is balanced.

5. ACID/BASE NEUTRALIZATION TYPE OF DOUBLE REPLACEMENT When an acid reacts with a base, water and a salt are produced. HCl + K(OH) H(OH) + KCl H(OH) is water! (H 2 O) KCl is an ionic compounda salt! Switch Places

6. SOLID OR SOLUBLE? When a double replacement reaction forms a SOLID, use the solubility rules on the back of your periodic table to tell which product is solid and which product is soluble. 3 AgNO 3 (aq) + K 3 PO 4 (aq) 3 KNO 3 + Ag 3 PO 4 Rules 1 and 5 (aq) (s) 3 (NH 4 ) 2 S (aq) + 2 AlCl 3 (aq) 6 NH 4 Cl + Al 2 S 3 Rules 1or 3 and 5 (aq)(s)