Sept 13: answer the questions pass the jar to the next student after you answer question 4. Do NOT open the

jar!

1. What protects your eyes?

2. Why is it important to make careful observations during a lab?

3. Give two examples of physical properties of motor oil.

4. Give two examples of physical properties of iodine in the jar

5. How can you tell if someone is in shock?

6. Which branch of chemistry involves the chemicals of living things?

7. Did the motor oil burn?

1. Goggles protect your eyes.

2. So you don’t mis-remember or forget what happened.

3. Yellow, viscous, less dense than water, hydrophobic.

4. shiny, dark crystalline solid with a brown vapor.

5. They may be pale or faint, with cold, moist skin and a weak, rapid pulse.

6. Biochemistry

7. No, we couldn’t get it to light.

1+ = 14%2+ = 28%3+ = 43%4+ = 57%5+ = 71%6+ = 86%7+ = 100%+.5 =7%

Where are we on the homework sheet?

• Homework #1 is class-work• Homework #2, sign the safety sheet. Make

sure you put an emergency number and an e-mail address on the safety sheet. I would prefer your parent’s e-mail.

• Begin Homework #3. 11 points until Tuesday.• Lab #3 also due Tuesday.• Leave your Chemistry Book at home, I will

keep copies in class if we need them.

Scientific Method• Your science fair project will help you

reproduce the scientific method.– Begin by observing the world around you.

What questions do you have about it?

Why didn’t the oil burn? Why doesn’t oil burn in cars unless the car is adulterated in some way?

What is already known about my question?

• Look in books, magazines and the internet. Write down on index cards, the following info…– Name of author– When it was published– In what source (magazine, book publisher, web-

address)– Any other identification, volume #, pages, ….

• Summarize what you read in the source on this card (or series of cards) You may choose to color code the cards according to author or topic, which-ever is more convenient.

Now that I know what others have done, what question can I

answer?

• Choose a question that can be answered by a small number of experiments. (between 1 and 3).

• Remember you will have to repeat your experiment at least three times to be sure it makes sense.

What am I testing?• You should have two variables. One, the

independent variable is what you will decide upon.

• The other variable is what you will measure. If you know the values of this variable, you do not have an experiment – these will be determined by experimentation.

Example: The oil in lab didn’t burn, but oily rags do.

Two experiments can determine why.

1) vary the amount of oil on 1 cm2 rags to see how much is required to burn. (1 drop, 5 drops, 10 drops,…)

2) vary the amount of rag/paper to see how much is required to burn 2 drops of oil. (1 cm2, 2 cm2, 4cm2,….)

What exactly am I looking for?

• Determine what you will measure. Oil burns at a VERY high temperature, paper burns at a low temperature. You can look at the color of the flame, how much moisture remains, the amount of heat generated.

• The question needs to be CLEARER!

Did my data make sense?

• If it did, great, graph your data and write up your results and conclusion.

• If not, ask…• Why doesn’t it make sense?• What should I do to see if what I

measured actually tests what I was hoping to test?

How do I know what type of graph to make?• If you are comparing

amounts, you should make a line graph.

• If you are comparing qualitative measures to quantitative you probably want a bar graph.

Exp A Exp B

Heig

ht

in

mm

Plant Growth

What should be in my conclusion?

• Does my data confirm my hypothesis?• How do I know?• What other experiments would I like to

follow up with?• Does what I found match what other

scientists have found?• Explain each of the above thoroughly.

Am I done?• No• You need to make a references

cited page.• You need to check out your paper

as a whole and make sure that it is your best work.

Am I done?• Now you are done!

Answers to Homework #3

• matter• inertia• energy• potential energy• kinetic energy• radiant energy• law of conservation

of mass

• Anything that takes up space or has volume

• the tendency of an object to resist a change in motion.

• the ability to do “work”.

• etcetera

Write definitions to vocabulary words

Next: Write sensible sentences.

• Matter. In Chemistry we study the properties of matter.

• Inertia. One of the properties of matter is inertia. Inertia is the property which makes it necessary to wear a seatbelt when I am in a car.

• etcetera.

Do # 6-11 page 186. What is inertia: Inertia is the tendency

of an object to resist a change in motion. For example,when a car is in motion, itdoesn’t stop immediatelywhen the brakes are applied.

7. Define potential, kinetic and radiant

energy.• Potential Energy is

the “ability” to do work.

• Kinetic energy is the energy of motion.

• Radiant energy is energy transmitted by electromagnetic waves.

8. What are the conservation laws of mass, energy and mass

energy.• Conservation , in Chemistry means that

whatever you begin with, still exists at the end. So, the law of conservation of mass states that if you begin with 10 pounds of cake batter, and you weigh the mass of the cake and the gases that escape as the cake is cooked, you will find that there are 10 pounds of cake + gases.

• The law of conservation of energy states that if you have 100 Calories, you can use 100 calories.

• The law of conservation of mass/energy states that both the former laws are true, but in nuclear reactions, when mass is converted to energy, the amount of energy “formed” is related to the amount of mass “lost” by Einstein’s equation E = mc2. No matter or Energy is un-accounted for.

9. What is Chemistry• Chemistry is the

study of the inter-relationships of the structure and properties of matter.

• What do substances do, and how do they do it?

10. What is the difference between a chemist and

chemical engineer? • Chemists do

research to develop new materials; chemical engineers develop ways to produce those materials in large quantities.

11. Differentiate between matter and energy.

• Matter is “stuff”, matter HAS energy (at least potential energy).

• Energy is like a verb, it has the ability to make changes occur. Energy can be harnessed to do work.

Selected Books• “Absolute Zero” by John

Shachtman• “A Short History of Chemistry” by

J.R. Parrington.• “Chemical History Tour: Picturing

Chemistry from Alchemy to Modern Molecular Science” by Art Greenberg.

In case you want to read something “good for you”.

Are Chemicals Dangerous?

• Some are… Strong acids and bases cause burns. Oxidizers may contribute to the development of cancer.

• Some are only dangerous in excessive quantity…. water is a chemical, air is made of chemicals, table salt, NaCl, is a chemical.

Hydrochloric acid, Sulfuric

acidSodium

hydroxide, lye

nitrates in bacon and hot-dogs, BHT, …

Nitrogen gas (80%),Oxygen gas (18%),

Carbon dioxide, water, etcetera

The Branches of Chemistry

• Chemistry is the study of the composition, structure, and properties of substances and the changes they undergo.– Organic Chemistry- the study of substances

containing Carbon and hydrogen, hydrocarbons like oil, plastics….

– Inorganic Chemistry- the study of the substances which do not have hydrocarbon “backbones”. (like acids, bases, salts, metals, nonmetals, metalloids,…)

– Physical Chemistry – the study of the properties, transformations, and interrelationships of energy and matter. (Chemistry math)

– Biochemistry – the study of substances and processes that occur in living things. (enzymes, vitamins/co-factors, genetic material)

– Analytical Chemistry – the identification of substances and qualitative determination of the composition of materials.

Don’t forget to keep studying

this every night!

Extra Credit (10 points) For each branch of Chemistry findat least two jobs where this branch would be your primary category.Use journals, encyclopedia’s, the internet… Justify your choice.