Acid/Base Chemistry Chapter 12 (Topic 5) Please note that the chapter does not go in sequence with our lecture material, but you must still understand the concepts Science 10 CT05D01 Resource: Brown, Ford, Ryan, IB Chem

Topic 05 – Acids/Bases  5.1 Solutions  5.2 Definitions of Acids and Bases  5.3 Properties of Acids and Bases  5.4 Calculating pH, pOH, H+, OH-  5.5 Neutralization equations  5.6 Titrations  We will come back to Topic 04 (Redox) following the completion of Acids/Bases

5.1 - Solutions  Define solute, solvent, solution, suspension, homogeneous, heterogeneous  Determine the molarity of solutions, given any of the two variables  (M = mol / L)  L = dm3  Calculate the dilution or concentration of solutions  (M 1 x V 1 = M 2 x M 2 )  Solubility and solubility curves

5.2 - Definitions of Acids and Bases  Arrhenius: Acids donate H +, Bases donate OH - ions in solution  Lowry/Bronsted: Acids donate a proton, Bases accept a proton (H + )

5.3 Properties of Acids and Bases  Acids (donate H +, turn litmus red, corrode active metals, neutralize bases, taste sour)  Bases (donate OH -, turn litmus blue, denature protein, neutralize acids, taste bitter

5.4 Calculating pH, pOH, H +, OH -  Calculate the concentration of ions (H + and OH - ) and acidity (pH and pOH) of strong acids and bases  Calculate the above of a mixture of strong acids and bases

5.5 Neutralization equations  Balance simple acid base equations  Conjugate Acid/Base pairs

5.6 Titrations  Complete titration calculations  (M A x V A = M B x V B )  Identify the parts of a titration curve  Buffer action of weak acids and bases

5.1 - Solutions  The solute is the material in the smaller amount that is being dissolved  The solvent is the material in the greater quantity in which the solute will dissolve. Water is the universal solvent, but other organic solvents such as ethanol are common as well  The Solution is a dissolved homogeneous mixture of two compounds

5.1 - Solutions  A suspension is found in a heterogeneous solution, that is due to the presence of insoluble particles added to the solvent material.  Turbulent water, and many powders (often protein shakes) can be insoluble

5.1 - Concentration

5.1 - Solutions  In order to solve for molarity we will often have to make mole conversions  Do you remember how to convert between moles and grams, grams and moles, mole and molecules, molecules and moles?  How do you calculate the molar mass of a compound?  What is avogadros number?  How would you convert from mL to L, L to mL?

Moles to Mass (use Molar Mass) Moles to Volume (Molar Volume of a gas 22.4) Moles to Molecules (use Avogadro’s Number)

Simple Conversions: 80. g CuSO g CuSO 4 1 mol CuSO 4 = 0.50 mol CuSO mol CuSO g CuSO 4 1 mol CuSO 4 = 80. g CuSO 4 - Mole / Mass Conversions - Use the Molar Mass of a substance to convert from Moles to Mass and Mass to Moles Mass to Moles  Moles to Mass 

2 mol CuSO x10 23 (mc) CuSO 4 1 mol CuSO 4 = 1.2x10 24 (mc) CuSO 4 = 2 mol CuSO x10 23 (mc) CuSO 4 1 mol CuSO 4 1.2x10 24 (mc) CuSO 4 Simple Conversions: - Mole / Molecule Conversions - Use Avogadro’s Number : x molecules (mc) in one mole of the substance Moles to (mc)  (mc) to Moles 

5.1 – Molarity Example

 What is the molarity of a solution containing 1.25 moles sodium chloride in 345 mL of solution?  What is the molarity of a solution containing 3.0 g potassium chloride in 500 mL of solution

5.1 – Dilution of Solutions  To dilute means to decrease the concentration by increasing the solvent amount  Sweet tea is too strong, add water  To concentrate means to increase the concentration by decreasing the solvent amount, or adding more solute.  Boil salt water  Add more Gatorade mix to your drink

5.1 – Dilution of Solutions

5.1 - Types of solutions  Saturated Solution – contains the maximum amount of a solute that will dissolve in a given solvent at a specific temperature  Unsaturated Solution – contains less than solute than it has capacity to dissolve.  Supersaturated Solution – contains more solute than is present in a saturated soln.

5.1 - Crystallization  Crystallization is the process in which dissolved solute comes out of solution and forms crystals  Usually occurs with a drop in temperature

5.1 - Changing the Temperature of Solutions  Remember, a saturated solution is defined at a ‘specific temperature.’  If the temperature is changed, the solvent can hold differing amounts of solute.  We can demonstrate how this might happen by using a solubility curve.

TEMPERATURESOLUBILITY in grams/100 ml of water CoCo KClKNO 3 NH

5.1 - Solubility Curves  Gases decrease in solubility with an increase in temperature  Solid and liquid solubility increases