Physical Science Stratton Tasty Solution Nature of Solutions Solution Chemistry Conductivity Inquiry Conductivity Alka-Seltzer Lab 1 Alka-Seltzer Lab 2 Rates of Solution Solubility Graph Physical Science Stratton Solubility Graph Lab Acids and Bases Cabbage pH Lab Acid Rain WebQuest Heartburn Lab Eggshell Titration

Tasty Solution Place one of the candy pieces in your mouth without chewing or moving your tongue around. Record the time that it takes for this candy piece to dissolve.

Tasty Solution Place a second candy piece in your mouth, this time moving your tongue, but not chewing. Record the time it takes to dissolve this candy piece.

Tasty Solution Place the third piece of candy in your mouth and chew it. Record the time to dissolve this third piece of candy.

Nature of Solutions solution Parts Types a. homogenous b. well mixed a. solute b. solvent c. ex. kool-aid Types a. aqueous b. tincture

Assignment: Make a list of 10 common solutions and determine solute and solvent for each

Conductivity Inquiry Materials: 1 graduated cylinder 1 beaker 1 spoon or glass stir rod 1 balance access to poled lightsocket Challenge: Find what types of solution are conductive and at what levels those solutions are conductive. Day 1: Make a procedure and have it critiqued Day 2: Carry out your procedure Day 3: Present your findings to the class

Conductivity a. ions b. water c. electrolytes

Alka-Seltzer Reactions: The effects of temperature on rate of solution Adapted from http://www.alka-seltzer.com/as/experiment/student_experiment1.htm

Hypothesis & Prediction Changing the temperature of the solution will effect rate of solution. Prediction: (discuss with your lab group and write)

Materials 3 original Alka-Seltzer tablets 3 250 ml beakers Graduated cylinder Thermometer Stopwatch Mortar and pestle Source of hot water Ice cubes

Procedure Design a procedure to test the hypothesis using the materials listed on the previous slide. Turn the procedure in for critique and change it if necessary. Be sure to design data tables for measurements you will be collecting.

Alka-Seltzer Reactions: The Effect of Particle Size on Rate of Reaction Adapted from http://www.alka-seltzer.com/as/experiment/student_experiment1.htm Using any of the materials from the last lab, prepare a procedure and data tables to test the hypothesis below. Hypothesis: Changing the size of the solute particles will effect rate of solution. Prediction: Procedure: Submit for critique (be sure to include data table)

Details of Making Solutions Solution Process a. molecules separate b. molecules are moved apart c. solute and solvent attract

Details of Making Solutions Changing rates of solution a. stir b. powder c. heat

Details of Making Solutions solubility a. solubility b. depends on solute and solvent c. main factors d. temperature e. pressure

Solubility Graph

Concentration a. dilute b. saturated c. unsaturated d. supersaturated

Solubility Graph

Solubility Graph Lab Materials: Procedure: Balance with weigh boats Hot plate water baths on it Sugar Salt Thermometer Water Test tube Glass stir rods Procedure: Write a procedure, using the materials given to gather data that will enable you to create a solubility curve for 2 solutes (salt and sugar) in water.

Acids and Bases Acids Bases 3. pH scale a. Donate H ions b. common acids Bases a. contain hydroxide ion (OH-) b. common bases 3. pH scale a. measures b. 0-14 c. Indicator papers d. Indicator liquids e. pH meters

Cabbage pH Indicators Day 1 Materials: Pipets Test tubes with racks Cabbage Juice Buffers of various pH Challenge: By the end of the lab period, your group should have a procedure ready that describes how to use cabbage juice to test the pH of household chemicals using the same materials as you did today (on day 2).

Acid Rain Webquest Introduction Why are the trees dying? How come there are no fish in the lake? Why does the paint on my Dad's car look so bad? Where does that terrible rotten egg smell come from in our school yard every Spring? The answer to these questions is simple; acid rain is responsible for many of the serious environmental problems facing us today. While the answer may be simple, solving the acid rain problem is not.

Acid Rain Webquest The Task A local citizens' group has hired you, and a group of other researchers, to investigate acid rain. You will take on the role of either a Chemist, or Biologist and examine the issue from that perspective. Within your group, decide who is going to assume the following roles. Use the questions appearing under each role to assist you in your research. You are responsible for completing only the questions in your section and working with your partner to come up with suggestions on ways to reduce acid rain. Your final product will be a short paper in paragraph form based on the data from yourself and your partner.

Where to Turn for Heartburn Evaluating the effectiveness of antacids Adapted from Prentice Hall Biology Exploring Life Lab 4A, 2004

Question: Which antacid is most effective in neutralizing acid?

Materials: Antacid medications (2 tablet types) Plastic bag Clear plastic cups or beakers Masking tape Graduated cylinder Water 2 plastic spoons transfer pipette pH strips vinegar (weak acid)

Procedure With your group, write a procedure using some or all of the materials to answer the question. Make data tables for any measurements you will make. Turn you procedures in for critique. Be prepared to share your results with the class later in the week.

Acid/Base Titration of an Eggshell From http://chem. lapeer During the 1960's and 70's the United States used a pesticide called DDT extensively. Unfortunately, the run-off from this pesticide entered our waterways and eventually into many of our wild birdlife. DDT affected the population by weakening the eggshells which would break before hatching. An example of this devastation was the American Bald Eagle whose population was as low as 400 mating pairs in the lower 48 states. The pesticide has been banned in the United States and the Bald Eagle is no longer on the endangered species list. One method of monitoring the strength of the egg is by determining the percent calcium carbonate in the eggshell. This can be accomplished through an acid/base titration method.

Procedure: Day 1 Clean and label a 150 ml beaker. Weigh the clean, dry beaker and record this amount onto your data table. Procure an egg from me. Remove the white and the yolk from the egg and dispose of them down the drain. Wash the shell with distilled water and carefully peel all the membranes from the inside of the shell. Discard the membranes. Place ALL of the shell in the preweighed beaker and dry the shell in the oven overnight.

Procedure: Day 2 Acquire a buret. Fill the buret with NaOH. Run out enough NaOH from the bottom to remove any air bubbles from the tip of the buret. Refill the buret to the 0.00 ml mark and record this amount onto the data table. Clean a 250 ml beaker and pipet exactly 25 ml of 1.0 M HCl into this beaker. Add approximately 50 ml of distilled water and 2 to 3 drops of phenolphthalein. Mix well. Slowly add the NaOH into the beaker until a slight pink color remains throughout the beaker. Record the amount of NaOH added. Determine the Molarity of the NaOH. . . . .

Procedure: Day 2 Take out the eggshell from the oven and cool to room temperature. Reweigh the beaker with the eggshell and record this weight onto the data table. Determine the weight of the eggshell. Place the eggshell in a mortar and grind it into a powder with the pestle. Weigh out 0.2 grams of the eggshell and place it into a clean dry 250 ml beaker. Pipet 50 ml of HCl and add this to the beaker. Stir for 5 minutes. Titrate this mixture with the NaOH. Determine the number of moles of HCl left in solution.

Calculations: Determine the moles of Calcium Carbonate in the mixture. Determine the percent calcium carbonate in the entire eggshell. The reactions taking place are: 2 HCl + CaCO3 -------------> CaCl2 + H2O + CO2 HCl + NaOH _________> H2O + NaCl