CHAPTER 8 SOLUTIONS AND BASES

I. FORMATION OF SOLUTIONS SECTION : 8.1 I. FORMATION OF SOLUTIONS

A. Dissolving and Solutions Solute - substances that dissolves Solvent – dissolves the solute Substances dissolve in water in 3 ways: 1. dissociation – ionic compounds separate into ions 2. Dispersion – breaking into small pieces and spread 3. Ionization – gain or lose electrons

B. Properties of Liquids Solutions 1. Conductivity 2. Freezing/Boiling point- salt spread on roads lowers the freezing point of water 3. Heat of a Solution – during the formation of a solution, energy is either released or absorbed

C. Factors affecting rates of dissolving 1. surface area 2. stirring 3. temperature

II. Solubility and Concentration Section 8.2 II. Solubility and Concentration

A. Solubility Solutions are described as saturated, unsaturated, or supersaturated, depending on the amount of solute in a solution. The maximum amount of a solute that dissolves in a given amount of solvent at a constant temperature is SOLUBILTY Expressed in grams of solute per 100 grams of solvent Ex. Table salt 36.0 g Baking soda 9.6g Sugar 203.9g

1. Saturated solutions Contains as much solute as the solvent can hold at a given temperature 2. Unsaturated – has LESS than the maximum amount of solute that can be dissolved 3. Supersaturated – contains more solute than it could normally hold at a given temperature Very unstable Page 236

B. Factors affecting solubility 1. Polar/nonpolar – water - polar and oil- nonpolar (don’t mix) Polar dissolves polar Nonpolar dissolves nonpolar 2. Temperature – add sugar to cold tea?? 3. Pressure – carbonated drinks

C. Concentration of solutions Solution is the amount of solute dissolved in a specified amount of solute 1. Percent by volume 2. Percent by Mass 3. Molarity Number of moles of a solute dissolved per liter of solution

III. PROPERTIES OF ACIDS AND BASES SECTION 8.3 III. PROPERTIES OF ACIDS AND BASES

A. Identifying Acids Compounds produce hydronium ions (H3O) when dissolved in water Sour taste Reactivity with metals Ability to produce color changes in indicators

B. Identifying Bases Compound that produces hydroxide ions (OH) when dissolved in water Bitter taste- unsweetened chocolate Slippery Feel – wet soap Color change in indicators

C. Neutralization and salts The reaction between an acid and a base The neutralization reaction between an acid and a base produce a salt water

E. Proton donors and acceptors Acids can be defined as proton donors, and bases can be defined as proton acceptors

STRENGTH OF ACIDS AND BASES SECTION 8.4 STRENGTH OF ACIDS AND BASES

A. The pH scale

A. pH scale (cont) The lower the pH value, the greater the H3O ion concentration in solution is. The higher the pH value, the lower the H3O ion concentration is. Acids ph level - less than 7 Based ph level – greater than 7 7(neutral) What is the pH of pure water?

B. Strong acids and bases 1. Strong Acids - When strong acids dissolve in water they ionize almost completely Ex. Sulfuric acid, H2SO4, and nitric acid, HNO3 2. Strong Bases – strong bases dissociate in water almost completely Ex. Calcium hydroxide (Ca(OH) 2 ) potassium hydroxide (KOH)

C. Weak acids and bases Weak acids and bases ionize or dissociate only slightly in water 1. Weak acids – citric acid, orange jucie, 2. Weak bases – toothpaste, and shampoo

3. Buffers A buffer is a solution that is resistant to large changes in pH.

D. Electrolytes Substance that ionizes or dissociates into ions when it dissolves in water The resulting solution can conduct electricity Strong acids and bases are electrolytes

THE END