HW #6 for 10/22

1) HW #6 pg. 90 #56, 60, pg. 91 #6-9
2) Parent conference tomorrow night 10/22 from 4:30-7

HW #5 for 10/20

1) HW #5: pg. 83 #5, pg. 89 #46-48, 52
2) Parent conference night Thursday

Mystery Powders Lab

Mystery Powders                            

Objective: To identify each of the powders through your observations and their physical or chemical changes.  Keep in mind the signs of the chemical changes that we have talked about.

Procedure:

1. Place a small amount of Mystery A into 4 three of your wells in your testing tray. 

2. Write down your observations of the color and texture for Mystery A.

3. Add about 3 drops of water to one well and observe what happens, write down your observations and write P for a physical change and C for a chemical change. You may mix it with a toothpick.

4. Add about 3 drops of vinegar to a new well and observe, write observations.

5. Add about 3 drops of iodine to your last well and observe, write observations.

6. Repeat the steps with Mystery B, C, D and E. Wash out your testing tray as needed; do not dry your testing tray.

7. Then ask Ms. Cotta to light your candle. Make 5 aluminum foil boats and place a small amount of Mystery A into one, B in a second one and so on.  Hold over the candle with the clothespin and write down observations. Do not forget to write P or C for type of change.  Throw away aluminum foil boats when finished and blow out candle.

	Mystery A	Mystery B	Mystery C	Mystery D	Mystery E
Color and texture
Reaction w/ water (P or C)
Reaction w/ vinegar  (P or C)
Reaction w/ iodine  (P or C)
Reaction when heated  (P or C)

What are each of the five mystery powders:

A ______________    B ____________   C _____________  D _________________   E _____________

Questions to Answer:

1. What substances reacted with vinegar? What is your evidence?

2. Which substance was not as soluble (dissolve) in water as well as the others?

3. What substances produced any odors when burned?

4. What substances had any movement when burned?

5. Why is it good lab practice not to taste or smell any substances found in the lab?

6. What is the definition of a chemical change?

7. Which of the substances underwent a chemical change? Give at least three examples. Explain why each is a chemical change.

8. What is the definition of a physical change?

9. Which of the substances underwent a physical change? Give at least three examples.  Explain why each is a physical change.

Procedure: Now you need to figure out what each of the mystery combinations are. #1 and #2 are both two of the substances mixed together. Use the same procedure that you used before.

	Color & texture	Reaction w/ water	Reaction w/ vinegar	Reaction w/ iodine	Reaction when heated
Mystery #1
Mystery #2

What are the two mystery powders that are mixed in Mystery #1? _______________________________________

What are the two mystery powders that are mixed in Mystery #2? _______________________________________

HW #4 for 10/19

HW #4: pg. 223 exer. 7.1 (yellow box), pg. 223 #1-4

HW #3 for 10/19

1) HW #3 pg. 83 #2-3, pg. 89 #45, 48, pg. 91 #6-7
2) Don't turn in HW until Monday October 19th
3) Take Home Lab #2 due on Monday October 19th as well.  It is published on the website as well

Take Home Lab #2

Take Home Lab #2: Investigating an Urban Legend

Question: Are you taller in the morning than at night?

Safety: Keep the sealed box of materials out of the reach of children. Your partner should not stand on an unstable object if he or she is shorter than you.

Materials: Pencil, ruler

Procedure: In this lab, you will investigate what may possibly be an urban legend. Some say that when you wake up in the morning, you are taller than you are later in the day. You will test this hypothesis by measuring your height as soon as you get up in the morning and then again at the end of the day. The difference, if any, will be small, so it is important that you control all possible variables and measure as accurately as possible.

1. Be sure that your shoes are off and you are standing on level ground. Have someone mark your height with a small mark on a wall or doorway, making sure that the pencil is completely level.  This is easier if the other person is taller than you. Do not make permanent marks on the wall—use a light pencil mark or tape.

2. Use your ruler to measure carefully the height of the mark from the floor.

3. Repeat this procedure again at the end of the day before you go to bed. Compare your mark in the morning to your new one at night. Measure carefully the new height. If there is an effect, it will be a small one.

4. Repeat the procedure on several days and try to find other volunteers to do the same.

Hypothesis:

1. Write a hypothesis whether you think you will get taller or shorter by the end of the day. Explain your reasoning to explain what you think will occur.

2. DATA:

Your data:                                                           Volunteer name: ________

Day one:

Height in the morning _______ cm                          morning _______cm

Height in the evening _______cm                             evening _______cm

Day two:

Height in the morning _______ cm                           morning _______cm

Height in the evening _______cm                             evening _______cm

Day three:

Height in the morning _______ cm                           morning _______cm

Height in the evening _______cm                            evening _______cm

Post-Lab Questions:

3. Is it true that you get shorter later in the day? Explain how you came to this conclusion. Use your data

4.  How would you explain this phenomenon if it is true? How could you test your hypothesis?

5. Devices to hang upside-down from your ankles used to popular for relieving pressure in your spine. Could this possibly work? Will it make you taller in the long run? Explain.

HW #2 for 10/13

1) HW #2 pg. 219 #1-3, pg. 234 #1, 3-4
2) Composition books due for Period 5 & 6 this week
3) Take Home Lab #2 due Mon. 10/19