Acid/Base Station Review Titration Calculation Notes and Demo

Evaluation/Assessment: Objective: Today I will be able to: Define an acid and base using the arrhenius and lewis definitions Determine the pH of a household substance using indicators Calculate the pH and pOH of a solution using pH scale calculations Correctly name acids and bases Calculate the concentration of an unknown acid by using titration Evaluation/Assessment: Informal assessment – student interactions at the stations Formal assessment – analyzing student responses to the stations and exit ticket Common Core Connection Demonstrate Independence Build Strong Content Knowledge Make sense of problem and persevere in solving them Reason abstractly and quantitatively Use appropriate tools strategically Attend to precision

Lesson Sequence Evaluate: Warm-Up Elaborate: Acid/Base Station Gallery Walk Evaluate: Acid/Base Review Engage and Explore: Titration Demo Explain: Titration Calculation Notes Elaborate: Titration Calculation Practice Evaluate Exit Ticket

Warm Up Name the following acids and bases HCl H2SO4 NH3 H2SO3 KOH

Objectives Today I will be able to: Define an acid and base using the arrhenius and lewis definitions Determine the pH of a household substance using indicators Calculate the pH and pOH of a solution using pH scale calculations Correctly name acids and bases Calculate the concentration of an unknown acid by using titration

Homework Wear Closed Toe Shoes for Lab B-Day (Thursday) A-Day (Friday)

Agenda Warm-Up Acid/ Base Station Gallery Walk Acid/Base Station Review Titration Demo Titration Calculation Notes Titration Calculation Practice Exit Ticket

Acid/Base Station Gallery Walk Travel to each station and check your answers (15 minutes to complete)

Acid/Base Review Game Find a partner. Get 1 whiteboard and 1 marker per partner. Answer the questions on the whiteboard. Each correct answer scores 1 point.

Properties of Acids and Bases Station 1 Questions

1. True or False Bases taste sour False (Acids taste Sour) http://www.nuts.com/chocolatessweets/hard-candy/wrapped/mega-warheads.html

2. True or False Acids make blue litmus paper turn red True Bases also turn red litmus paper blue

3. True or False Thinking of Acid, Base and Neutral substances… Only acids act as electrolytes and conduct an electrical current False Both acids and bases are electrolytes

4. True or False Bases react with metals to form hydrogen gas False Acids react with metals to form hydrogen gas

5. True or False Acids and bases neutralize each other when they react. This process destroys the properties of the acid and base. True

Indicators Station 2 Questions

1. True or False The indicator phenolphthalein turns pink in a basic solution. True

2. True or False An indicator usually changes color over a pH range.

3. True or False All indicators are liquid. False

4. True or False Some fruits and flowers can be used as indicators.

5. True or False A universal indicator is a blend of pH indicator solutions designed to identify the pH of a solution over a wide range of values. True

Litmus Paper Testing Station 3 Questions

1. True or False Litmus paper that changes from blue to red in a solution indicates that the solution is neutral. False Blue to red indicates an acidic solution.

2. True or False Orange juice is a solution that might change litmus paper from blue to red. True Orange juice is acidic.

3. True or False Blue litmus paper that changes to red shows that the solution has a pH of 3. False Litmus paper does not show pH values.

4. True or False Cleaner with ammonia is a solution that might change litmus paper from blue to red. False Cleaner with ammonia is basic. It changes red litmus paper to blue.

5. True or False Red litmus paper that changes to a wet red color indicates that the solution is basic. False Red litmus paper changes to blue in the presence of a base.

pH Scale Station 4 Questions

1. True or False Bases have higher pH values than acids on the pH scale. True

2. True or False Hydronium ions can be written as H2O+ False Hydroniums ions are written as H3O+

3. True or False The equation to determine pH is pH = log[H+] False

4. True or False pH can be converted into a pOH value by using the equation pH + pOH = 14 True

5. True or False pH can be written as H+ ions or H3O+ ions. True

Arrhenius vs Bronsted Lowry Acids and Bases Station 5 Questions

1. True or False An Arrhenius acid is a substance that when added to water increases the number of OH- ions in the water. False Arrhenius acids increase the number of H+ ions in the water.

2. True or False According to the Bronsted Lowry theory, an acid is a "proton donor" and a base is a "proton acceptor.” True

3. True or False NaOH is an example of an Arrhenius base. True

4. True or False HF is an Arrhenius acid. True

5. True or False NaOH is an example of an Arrhenius, and a Bronsted Lowry, base. False

pH Paper Testing Station 6 Questions

1. True or False pH paper turns red or blue. False pH paper can change a variety of colors.

2. True or False A neutral substance has a pH of 7. True

3. True or False An acidic substance can have a pH of 6. True

4. True or False A basic substance can have a pH of 5. False

5. True or False pH paper dipped into a substance shows results as a color change and a numerical value. True

Acid Naming Station 7 Questions

1. True or False If the anion of an acid ends in “ide” you name the acid hydro____ ic acid. True

2. True or False If the anion of an acid ends in “ite” you name the acid _______ ic acid. False Anions that end in “ate” are named ____ ic acid

3. What is the Acid Name? HF Hydrofluoric acid

4. What is the Acid Name? HNO2 Nitrous acid

5. What is the Acid Name? HC2H3O2 Acetic acid

Naming Bases Station 8 Questions

1. Name this Base LiOH Lithium hydroxide

2. Name this Base KOH Potassium hydroxide

3. Name this Base Ca(OH)2 Calcium hydroxide

4. Name this Base Ba(OH)2 Barium hydroxide

5. Name this Base NH3 ammonia

pH calculation Worksheet Complete the practice at your desk. Ms. Ose will grade the assignment for accuracy

Titration Notes/Demo/Curves

Titration is a neutralization reaction Products are salts and water Salt produced can be slightly acidic, slightly basic or neutral (Depends on acid strength)

Goal of Titration Procedure use to determine the concentration of an unknown acid or base Standard solution – solution with the known concentration

A solution is titrated until the concentration of acid=base This is called the Equivalence Point If an acids and bases are transparent, how can we determine when the concentrations are equal? Use phenolpthalein as an indicator Turns fushia in a basic solution Stop titrating when the solution turns light pink This is called the endpoint

Watch Ms. Ose’s Titration Demo

In the perfect world…. Equivalence point = Endpoint Our endpoint will be a little beyond the equivalence point since we have to see the color change

Now we can calculate the concentration of an unknown acid Ms. Ose will walk you through a guided notes outline to complete the titration calculation. Problems not completed in class will become your homework.

Exit Ticket Write the steps you will take to have a successful titration next class