Unit 1 Loose Ends and Test Review Unit 1 Loose Ends and Test Review

Unit 1 Loose Ends and Test Review

Objective A (remember, the objective refer to the Study

Guides)http://www.magazine-agent.com/officials-logic-problems/magazine

Look at the following numbers. How easy would it be to memorize this list and regenerate it in a week or so on a quiz?

1, 3, 5, 11, 21, 43, 85, 171, 341, 683, 1365, 2731, 5461, 10923, 21845

Pretty hard? Pretty Easy? Why?

Easy huh? OK, what’s the next number in the sequence? How about the next 5 numbers?

1, 3, 5, 11, 21, 43, 85, 171, 341, 683, 1365, 2731, 5461,

10923, 21845http://www.antiqueradiomuseum.org/RR%20Rule%20Book%20for%20CMSP&P%20RR.jpg

The numbers don’t seem to follow any kind of pattern.

But, what if you knew a rule? It wouldn’t just be memorization then.

OK, good point! The rule is: Start with 1. Double and add 1. Double and subtract 1. And so on.

You just wish it was that EASY!

Learn HOW to do the problem; don’t just memorize the

answer!http://familyfun.go.com/Resources/printable-previews/previews/beaver_memorygame_august2.jpg

Doesn’t “knowing the rule” make the list easier to memorize?

You don’t have to memorize a bunch of unrelated numbers.

IF YOU KNOW the rule, you can generate the number list on the test easily. Anytime! Anywhere!

Don’t

Can you make sense out of NONSENSE?

Force Hour Upon Neigh

KoranForce Cis Shun

Heaven Fodder Count

Ye Brat Anent

Sago Farce Anew

Figured it out yet?

The Gettysburg Addresshttp://www.old-picture.com/defining-moments/pictures/Abraham-Lincoln-Antietam-Battlefield.jpg

http://en.wikipedia.org/wiki/Gettysburg_Address

“Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.”

Being able to look at something new, and make sense of it is an important skill for the rest of this course.

Yes, Ms Rackley, I know this was Antietam, but it’s a nice picture.

Objective Ahttp://www.tvgasm.com/newsgasm/Bill-nye.jpg

In Chemistry, when we have numbers, much of the time we do one of three things:

Multiple 2 x 3 Divide 2 / 3 Divide 3 / 2

If you can figure out which operation to do when, you can actually solve the problem. That’s our goal.

What would Bill Nye do?

Answer: nothing because he just died.

Units TELL you the right ANSWER!

If your units don’t work out right, your answer is wrong.

Don’t just ignore wrong units. It is a big clue for you.

LISTEN to the units!

Qualitative and Quantitative Data

Qualitative (think quality) These are observations usually. It’s blue. It’s hot. It’s cool. It’s smells like rotten eggs. Remember to look for qualitative date when you do your

lab experiments.

Quantitative (think quantity or amount) These are the numbers you measure. 5.0 g of baking soda. 2L of diet Coke. 4.5 moles of CO2.

Remember to record quantitative data in your lab notebook when you do experiments too.

Objective C…Error

We will discuss error primarily in our labs. Always include a discussion of any errors that happened in your experiment in your “Analysis of Data” section of your lab report.

What kind of errors can you have in your labs?Two kinds:

RandomSystematic

Objective C…Errorhttp://www.budapesthotels.com/sitepic/error_button.png

http://images.intomobile.com/wp-content/uploads/2009/06/easy-button.jpg

Random errors are mistakes. You can take care to reduce or eliminate random errors. These usually come from being unprepared (not reading the lab prior to doing it), rushing to get done, and careless errors (like forgetting to do a step).

Systematic errors are errors that are present in your system. You can’t do anything about these. If your data is precise, but not accurate this might indicate that you had systemic error.

Easy Button

Error Button

Objective d…Significant Figures

When you take measurements in Chemistry class or in lab, you have to worry about how many significant figures (usually abbreviated as sig figs) you have.

What are sig figs? All the digits you can read and the first one you can

estimate.

Between 7.1 and 7.2, so record as 7.15. All 3 digits are significant, because you read the first 2 and estimated the last 1.


http://www.freefoto.com/images/2000/98/2000_98_1---Number-Zero_web.jpg

However, if you didn’t measure it, there are rules for figuring out how many sig figs something has.

RULE #1. All non-zero digits are significant.

So that means that the only thing you have to determine is whether or not the zeros are significant.

Significant?

Maybe or maybe not!


Rules are in the study guide.2. Zeros between non zero digits are

significant. So, 2.003 has 4 sig figs.3. Zeros at the end of a number AND to the

right of the decimal point are significant. So, 1.000 has 4 sig figs.

4. Zeros at the beginning of a number are never significant. So, 0.00034 has 2 sig figs.

5. Exact measurements or exact quantities have an unlimited amount of sig figs. Example 1 hour = 60 min. “1” and “60” both have an unlimited number of sig figs.


Adding/Subtracting Answer cannot have more sig figs AFTER the decimal point

than the number with the lowest number. Ex: 2.1 + 2.22 + 2.345 = 6.665 Answer can only have 1 digit after the decimal Correct answer = 6.7

Multiplying/Dividing Answer cannot have more sig figs than the number with the

lowest number of sig figs. Ex: 2.22 x 2.345 = 5.2059 2.22 has 3 sig figs and 2.345 has 4 sig figs. Answer can only

have 3 sig figs. Correct answer = 5.21

±1 sig figs off is usually OK. If answer should have 4 sig figs and you have 3, 4 or 5, I won’t mark it wrong.


http://www.tvguide.com/celebrities/stuart-scott/214001

But isn’t 50 and 50.0 and 50.00 and even 50.000 the exact same number?

Maybe, outside of chemistry class, but not in here.

Let me explain.

50 ≠ 50?

Wha-hap-happen?


50 means that your measurement is somewhere between 49 and 51.

50.0 means that your measurement is somewhere between 49.9 and 50.1



The more sig figs in your measurement, the more confidence you have that it’s “exactly” 50 mL or g.

Objective f…Densityhttp://www.stevespanglerscience.com/img/cache/bcb9b8db117ee64376aedaf7af3595ca/

sevenlayer-2-51908.jpg

Higher density layers on the bottom and lower density layers on the top.

Is oil more or less dense than water?

D = m / V

Objective g…Ice Floatshttp://www.dharma.org/ims/images/pi_ice_on_pond.jpg

Why does ice float?Why is this a good

thing?Ice is actually kind of

strange. Actually water is a very unique compound.

Most substances are more dense as a solid than they are as a liquid.

Ice is an exception.

Objective h: Measure your Kinetic Energy: Take Your Temperature!

http://www.avogadro.co.uk/miscellany/t-and-p/thermometers.gif

Kelvin temperature was defined to be a measure of the kinetic energy of the sample of matter. 0K is ABSOLUTE zero.

A sample of matter at 300K has twice as much kinetic energy as a sample of matter at 150K. Temperature is directly proportional to kinetic energy.

You must remember how to convert from °C to K and vice versa. It WILL be on the test.

The End

What is next?

Unit 2: Chapter 5, 28, 13, and 14.

We will do ALL of Chapter 5, but only portions of the other 3 chapters.

Documents

Unit 1 Loose Ends and Test Review Unit 1 Loose Ends and Test Review