Question of the Day Was the Wicked Witch a good chemistry student? Did she correctly and scientifically describe her demise? Day 3 2-25 1

Objectige / Essential Question How can we predict the solubility of a salt based on its ions?

Electrolytes and Nonelectrolytes Your cells use electrolytes, such as sodium and potassium ions, to carry electrical impulses across themselves and to other cells. An electrolyte imbalance can occur if you become dehydrated. When you exercise, you can lose water and electrolytes from your body through perspiration.

V. What are metathesis reactions? A. Metathesis reactions can also be called _______ ______________ reactions. B. The mixing of 2 solutions will result in a chemical reaction if _____ are _________ from the solution. double replacement ions removed

Metathesis (Exchange) Reactions Metathesis comes from a Greek word that means “to transpose.” AgNO3 (aq) + KCl (aq)  AgCl (s) + KNO3 (aq)

Metathesis (Exchange) Reactions Metathesis comes from a Greek word that means “to transpose.” It appears the ions in the reactant compounds exchange, or transpose, ions. AgNO3 (aq) + KCl (aq)  AgCl (s) + KNO3 (aq)

Solution Chemistry It is helpful to pay attention to exactly what species are present in a reaction mixture (i.e., solid, liquid, gas, aqueous solution). If we are to understand reactivity, we must be aware of just what is changing during the course of a reaction.

V. What are metathesis reactions? Ions can be removed from solution by any of 3 processes: 1. The formation of an __________ solid, known as a _____________ 2. The formation of either a weak ____________ or a ________________ 3. The formation of a ____ that bubbles out of the solution insoluble precipitate electrolyte nonelectrolyte gas

Precipitation Reactions When one mixes ions that form compounds that are insoluble (as could be predicted by the solubility guidelines), a precipitate is formed.

V. What are metathesis reactions? C. Examples Write the molecular, complete, and net ionic equations for these reactions that occur in water. 1. Magnesium nitrate and sodium hydroxide

V. What are metathesis reactions? C. Examples Write the molecular, complete, and net ionic equations for these reactions that occur in water. 2. Magnesium hydroxide and hydrochloric acid

Test = Monday 3-3

Postlabs due Wednesday 2-26. Due Dates period 1 Postlabs due Wednesday 2-26. Lab Reports and Presentations due Monday 3-3. Day 2 2-24

Postlabs due Thursday 2-27. Due Dates period 3 Postlabs due Thursday 2-27. Lab Reports and Presentations due Monday 3-3. Day 2 2-24

Question of the Day Day 4 2-26 What volume of 10 M HCl must be diluted to prepare 500 mL of 1 M HCl? Barium hydroxide has a low solubility, but is considered a strong electrolyte. Explain how this is possible. Day 4 2-26 15

Test = Tuesday 3-4

Objectige / Essential Question How can we predict the solubility of a salt based on its ions?

V. What are metathesis reactions? C. Examples Write the molecular, complete, and net ionic equations for these reactions that occur in water. 3. Chromium(II) acetate and nitric acid

V. What are metathesis reactions? C. Examples Write the molecular, complete, and net ionic equations for these reactions that occur in water. 4. Barium nitrate and sulfuric acid

Assignments Solubility Rules Handout 20

Solubility Rules

Test = Friday 2-8 for Period 3 Thursday 2-7 for Period 1

Presentations

Double Pd 1 2-1 Prepare 150 ml of 0.1M solutions of: BaCl2 CaCl2 SrCl2 LiCl 24

Test = Thursday 2-7 for both periods

Assignments Solubility Rules Handout 26

Solution Formation What factors affect how fast a substance dissolves?

Solution Formation Which dissolves faster sugar cubes or granulated sugar? Why the stirring? Sugar dissolves faster in hot / iced tea?

Solution Formation Like Dissolves Like The compositions of the solvent and the solute determine whether or not a substance will dissolve. Like Dissolves Like Factors that affect how fast a substance dissolves include: Agitation Temperature Particle size of the solute

Solution Formation Agitation Agitation (stirring or shaking) affects only the rate at which a solid solute dissolves. It does not influence the amount of solute that will dissolve. Agitation increases the rate of dissolving

Solution Formation Temperature Higher temperatures lead to an increased rate of dissolving. At higher temperatures, the kinetic energy of molecules is greater than at lower temperatures, so the molecules move (and mix) faster.

Solution Formation Particle Size of the Solute Smaller particles expose a greater surface area and so increase rate of dissolving. The more surface area of the solute that is exposed, the faster the rate of dissolving.

Which of the following will not speed up the rate at which a solid solute dissolves? A. Increasing the temperature B. Stirring the mixture C. Crushing the solute D. Decreasing the temperature

Quick Draw Molarity Net ionic equation Solute Dissociating Diprotic acids Spectator ions VcMc=VdMd electrolyte Strong acids mols/L salts Weak base

QUICK TALK NH3 Disperse Strong base Hydrogen bonding Solute Molecular equation Molarity Weak acid Solvent Tincture VcMc = VdMd Monoprotic

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