14 December 2010

Today we read about and discussed how energy is involved with changes in states of matter. For example, a substance changing from a liquid to a solid (aka freezing) or from a gas to a liquid (aka condensing). We also read about how freezing and condensation give up energy and are called exothermic. On the other hand, vaporization (boiling and evaporation), melting, and sublimation are endothermic, or require the substance to gain energy.

Here is another video to help students review the material we covered today: http://www1.teachertube.com/viewVideo.php?video_id=111175&title=States_of_Matter___Part_2&vpkey=&album_id=

In some classes, we discussed how this relates to the lab we did at the beginning of the unit. We looked at how our graphs compared to the graphs in the book and noticed that once the water started to boil at 100 degrees Celsius, the temperature stayed the same as the water boiled. Similarly, as we froze some water, the temperature stayed at 0 degrees Celsius until it had completely frozen. The classes that did not get a chance to discuss this will be discussing it tomorrow before we review for the test.

As we have come to the end of the unit on states of matter, we will be having a test on Thursday the 16th.

• Students should review p. 72-81 of their notebooks to prepare for this test.
• Left side activities should be completed for pages 74, 78, 80 in their notebooks.
  
• If they are looking at the online book (see my web page for the link under "Useful Links") it is Chapter 6.
• A Chapter Review will be given to the students on Wednesday (completed as homework) and we will go over it before the test.

December 7th in class

Here is a link to some very cool science interactive simulators. http://phet.colorado.edu/Just click on the "play with the sims" button.

We used one of these in class today. http://phet.colorado.edu/en/simulation/states-of-matter

a couple of others that will be useful in the future are:
Gas Properties
Build an Atom
pH scale

Publish Post

Monday in Class

After Mental Math and the warm up, today we started class by me giving directions on how to graph their data from Friday's lab. Students should graph time across the x-axis (bottom of the graph) and temperature on the y-axis (left side of the graph). This should be completed for homework. We may not get to it until Wednesday, but it needs to be completed for Tuesday, just in case we get to it.

Then, we looked at how the particles of a substance move depending on its state. We used a fill-in of guided notes as we watched the following video:

http://www.teachertube.com/viewVideo.php?video_id=111171&title=States_of_Matter___Part_1

Not all classes completed the notes and we will complete them tomorrow.

Monday in class

I hope everyone had a great Thanksgiving weekend!

Here is an electronic version of the practice in identifying chemical and physical changes we did in class today: http://www.quia.com/quiz/303980.html. Students should recognize that a chemical change creates a new substance and usually can not be undone. Physical changes can often be undone and the material stays the same.

Then, we took a look at how the properties of matter are used in technological design. Students should should be able to describe how certain properties of matter can effect choices for suitable materials for designing everyday technology.

Chemistry: The Study of Matter

Friday we kicked off our study about Chemistry and today we started to dig into some of the content. We discussed how everything is made of matter and all matter has both volume and mass. (4th period stopped here and will continue tomorrow.) Mass and weight, although often used interchangeably, are different. We finished up with a short demonstration about how greater mass means an object has more inertia.

Homework was assigned for tomorrow. Students should finish the inside section of today's handout. They may skip numbers 7 and 9. (They should have already answered 7 on the front and we did not discuss how to do number 9.) 4th period will be doing this assignment on Tuesday night, as we did not get to finish the material.

Change in the plan

Due to this week's short week, I am going to change the plan slightly. I am going to move the test to Wednesday. This means Monday will be a day of reinforcement of the concepts we learned last week. Tuesday will be review. Wednesday will be the Test.

The test will cover pages 46-53 in their notebooks. This is Chapter 4 in the textbook, which can be viewed on-line. See the link on my school web page.

Sorry it has been so long.

Sorry I have neglected the blog here, but I'm back. I hope everyone enjoyed their fall break!

Just before the break, we discussed the causes of ocean currents, both deep currents and surface currents. When we returned on Wednesday, we learned how currents can affect climate. As an example, several places in northern Europe have much milder climates than places at similar latitudes in North America and Asia. This is because the Gulf Stream and North Atlantic Drift carry warmer water in that direction. This, in turn, warms the air which gets carried on land and keeps the climate warmer.

Similarly, the California Current from the northern Pacific Ocean carries cooler water along the west coast of the U. S. This keeps the temperature from getting to hot and creates what we, often, think of as being typical California weather. Basically in the 60's and 70's year round. However, this is only typical on the coast, much of the land further inland is much hotter.

In general, warm currents flow away from the equator and cold currents flow toward the equator.

Thursday, we will be looking at tides. This should be mostly review from 6th grade science. Friday will be about waves and wave action on the shoreline. We should be able to cover all of this by Friday, have a review on Monday and take a test over ocean currents, tides, and waves on Tuesday. This may get pushed back a day so we will take our test the day before our day off. It just depends on how much the students remember.

Oh, and KSS is due on Friday this week instead of the usual Thursday. Same thing will apply for next week since we have Thursday off.