Acidic, Basic, or Neutral Solution How do make an acid or a base?

Group 1 or 2 Metals in Water K (s) + H2O (l)  Complete and Balance Rule: Alkali metals and Alkaline Earth Metals in water form bases!

Practice Problems 2 Na (s) + 2 H2O (l)  2 NaOH (aq) + H2 (g) Sodium in water Calcium in water 2 Na (s) + 2 H2O (l)  2 NaOH (aq) + H2 (g) Ca (s) + 2 H2O (l)  Ca(OH)2 (aq) + H2 (g)

Thermodynamics Review Cesium in water? + or – ΔH? + or – ΔS? + or – ΔG?

Metal Oxide in Water CaO (s) + H2O (l)  Balance General Rule: Metal oxide in water form basic solutions!

Practice Problems Na2O (s) + H2O (l)  2 NaOH (aq) Sodium oxide in water Na2O (s) + H2O (l)  2 NaOH (aq)

Nonmetal Oxide in Water CO2 (g) + H2O (l)  Balance General Rule: Nonmetal oxide in water form acidic solutions!

Nitrogen Dioxide in Water 2 NO2 (g)+ H2O (l)  HNO3 (aq) + HNO2 (aq)

Sulfur Oxides in Water SO2 (g) + H2O (l)  SO3 (g) + H2O (l)  +4 +6 General Rule #2: More positive charge on the nonmetal leads to stronger acid. +6

Practice Problems Cl2O (g) + H2O (l)  2 HClO (aq) Chlorine (I) oxide in water Chlorine (VII) oxide in water Cl2O (g) + H2O (l)  2 HClO (aq) Cl2O7 (g) + H2O (l)  2 HClO4 (aq)

SALTS IN WATER? NaCl(s) + H2O(l)  HCl(aq) + NaOH(aq) Would the dissolving of a salt in water cause the water to be neutral, acidic, or basic? NaCl(s) + H2O(l)  HCl(aq) + NaOH(aq)

ACIDIC or BASIC SALTS Using pH indicators (phenolphthalein, bromthymol blue, etc), determine if the following salts are neutral, acidic, or basic: NaBr Na2CO3 Pb(NO3)2 K3PO4 NH4Cl

Where do we get indicators?

Indicators to Use Phenolphthalein Bromthymol Blue Write the dissociation of each salt in water. Why are some acidic, neutral, or alkaline (basic)?