Tuesday, August 31, 2010

Tuesday

to be updated later

Tonight's homework is to finish the unit 2 Math Sheet - due tomorrow into the box
And box L on the green sheet

The Unit 2 Matter Test will be Friday. Packets will also be due at that time. 

Monday, August 30, 2010

Colligative properties, electrolytes, and dilutions... oh my!

Colligative properties are when the physical properties of a solvent are changed because of the number of solute particles added. We put salt on the roads in the winter because it lowers the freezing of point of water to below zero - so the ice will not refreeze in the roads unless it gets below negative four. In places north of here where it is really cold - they don't use salt because it will not lower the freezing point enough. 

Electrolytes conduct electricity and are important in our bodies because our brain sends electrical messages to our muscles. In chemistry, ionic compounds make the best electrolytes because they break apart into negative and positive ions that can carry electric current. I did a demonstration with some solutions showing how things like salt water can conduct electricity and sugar water will not.

We finished the demonstration by trying it with gatorade which does make the lighbulb glow, but really really dimly. It is true that gatorade has electrolytes in it, but it also has a LOT of sugar in it. Most high school students do not need to drink gatorade becuase they get enough electrolytes from their food, and if they are going to drink it, they should drink it after practice, not all day long. 

We finished class by discussing molarity and dilutions. Molarity measures the concentration of liquids. The formula for Molarity is 

Molarity = moles
                 liters

Dilutions are made by adding water to existing solutions. When a solution is diluted, the volume is increased, but the molarity (or concentration) decreases. This makes sense if you think about it. The more water you add to a colored solution like kool-aid, the lighter in color it will become. 

The formula for dilutions is MV=MV. For these it is ok to use milliliters for the volume. Students need to isolate whichever variable is not given. We will practice this math some more. 

Homework tonight is to finish up the dilution problems (4th only) and to work on boxes I and B on the green sheet. There will be a lab on Wednesday (wear appropriate clothing and shoes) and the Unit 2 Test will be Friday

Here is a little humor to finish the day...

Marshmallow Friday by Taylor K

This is an experiment dealing with physical and chemical properties & changes. We have Lucy (marshmallow on left) & Charlie (marshmallow on right) we recorded their physical properties in their original state, then placed them in the microwave for 1 minute and examined physical & chemical changes that take place.

Friday, August 27, 2010

Friday is for finishing things up

Today was a hodge podge, finish up, practice, and review day. Students started class with a jump in about phases and phase changes. We went over the homework and made sure their weren't any questions. We talked about density and worked through some density problems.

Third period took a small quiz and then finished up their Marshmallow Madness labs. It's pretty funny to see a class full of kids crowded around the microwave to watch marshmallows heat up. Marshmallows are mostly air and when air is heated, the particles move more and expand - so the marshmallows expand and blow up. When the microwave cuts off, the marshmallows shrink because as the air particles cool, they move less and less and contract. Third period finished with a quick review on a variety of concepts covered in this unit. Taylor, Taylor, Josh T, Brande, Kaleb and Tim are rock stars! Thanks also to Morgan and Shaun for contributing answers.

Some people think its funny to do chemical experiments on marshmallow peeps. Check this out. I think they are funny - I like the egg slicer myself.

Fourth period went over the small quiz and also discussed solubility graphs (see previous post). They worked through some graph problems with Zack demonstrating on the computer. Fourth period finished up with a rowdy game of whiteboard jeopardy. Josh G and Katelin were the winners with the most points, but everyone learned some things they forgot, and a good time was had by all.


Tonight's homework (for over the weekend) is to work on box F on the green sheet and to work on the vocabulary on the front of the packet. We are looking at a Unit 2 Test on Friday.

Thursday, August 26, 2010

Solutions Suspensions and Colloids

Today we started class identifying physical and chemical properties and changes. We watched a BrainPOP on physical and chemical changes and took the quiz. The amount of perfect scores was astounding.

For notes we covered solution, suspensions, and colloids. Solutions are homogeneous well mixed mixtures where a solute is spread out in a solvent. Suspensions are heterogeneous and will separate and settle over time because the larger particles are affected by gravity or perhaps the mixed substances have different densities. Colloids are weird because they should be suspensions, but the particles are so tiny that they constantly bump into each other and stay suspended.

We also looked at this solubility graph and answered a variety of questions. There are many ways to word questions based on this graph and students did well answering them.

We finished class by making observations of marshmallows. Students used their senses to make qualitative measurements and used rulers, balances, and calculators to make some quantitative measurements. The activity ends with microwaving a marshmallow - which is fun to watch. Fourth saw the magic today and third will see it tomorrow.

Tonight's homework will be boxes E and H on the green sheet

Are you smart enough chemistry-wise to understand this joke?

Wednesday, August 25, 2010

All Over the Place

Today we started class with a jump in that looked at the differences between elements and compounds and hte differences between substances (elements and compounds) and mixtures. We did a smidgen of notes to learn the differences between homogeneous mixtures (the same every time) and heterogenerous mixtures (different every time) and then did another sort that first broke things down into substances or mixtures and then further broke them down.

Next we did a Physical/Chemical Challenge with Tim, Taylor, and Josh T in third coming out on top, and in fourth Josh beat everyone, with April and Lucas close behind. Next we did a smidge of notes on density. We talked about what density is (the amount of stuff in a space), what it means when you mix things of different densities together (they separate into layers), and we practiced some density math problems. We finished class by combing liquids of varying densities to see which layers were the least and most dense.

Tonight's Homework is boxes C and D

Oobleck post by Danielle

Today in Ms.J's wild class we did a lab on solid, liquids, and gases.We got to play with oobleck and it was very disgusting. It was wet, but it would dry to your hand very fast. I have to say so far that this is my favorite lab. And I definitely understand solid, liquids, and gases better now:)

Oobleck by Katelin

Today we made some oobleck and it was loads of fun! We mixed corn starch and water together and made this amazing mixture. We did this experiment to learn about mixtures. It was really fun to play with and a super duper cool and fun lab! :)

Tuesday, August 24, 2010

Matter... and OObleck

Today students went over the differences between solids, liquids, and gases. This is material they should be familiar with, but we are reviewing it and going a little more in depth. We discussed what the particles look like, the densities, and how much energy they have. We also discussed phase changes and worked on two phase change graphs the students will see on the SOL, how to label them, and how to answer questions about them.

We also discussed matter (everything in the universe is made of matter) and how you can classify it as substances or mixtures. Substances can either be elements from the periodic table or compounds made up of more than one element. 

We finished class by doing a lab with oobleck. Oobleck is technically a non-Newtonian Fluid which is really hard to define in layman's terms. Scientifically it is also a colloid because the cornstarch particles are very tiny and evenly dispersed throughout the water, but will not settle out. Anyway.

The students mixed up their oobleck and then performed a series of tests to determine whether the oobleck was more like a liquid or more like a solid (they had to make a choice). Fun was had, messes were made, people were learning. Life was good. Here is a photo of Caroline (look at her mess!).

To watch a mythbusters about oobleck and how you can walk on it(!) - click here.

Homework for tonight are Boxes G and J on the green homework sheet

Monday, August 23, 2010

Solids Liquids and Gases

Today we discussed solids, liquids, and gases. We talked about the amount of energy the particles had and how the particles move. We discussed whether they had definite or indefinite volumes and shapes. We talked about why exactly we can't walk through walls, but why we can walk through gases and liquids.

Next we discussed the phase changes that happen between solids, liquids, and gases. These changes can be represented on one of two graphs. We talked about the graphs, labeled them, and and answered questions about them. We finished the day with a game of SWAT where the class was divided into two and one person from each team went head to head to be the first to swat the correct part of the diagram.

Tomorrow we will explore solid liquid and gases a bit more and also talk about matter.

HOMEWORK - Box A on the green sheet

Friday, August 20, 2010

Unit 1 Test

Today we started class with conversions involving some of the crazy things people do to get in the Guinness Book of World Records - like longest ear hair, skinniest waist, tallest man, etc. I think the one the kids thought was the weirdest was the lady who can pop her eyes out 12mm.

We went over last night's homework to see if there were any questions and then took the Unit 1 Test. Students seem confident about how they did and they will get them back on Monday.

Homework for this weekend is PEACH and involves solids, liquids, and gases as well as density.

Thursday, August 19, 2010

Review for Unit 1 Test

Today we went over the review sheet and answered any questions. Next students worked on identifying parts of the scientific method using some pretty ridiculous scenarios. In third, Tim and James finished on top and Tiffany and Sam were the highest in fourth. Next students worked on practice SOL questions related to the material in Unit 1. Tim and James were again on top, but in fourth April and Josh beat out Sam by two points.

It is Thursday so we took a quiz, as practice, to make sure students knew concepts and then we finished class with some practice conversions and train tracks math.

Tonight's homework is to make sure that the entire Unit 1 packet is complete and to finish all of the blue homework sheet.
Gummy Bear Labs due tomorrow
Unit 1 Test tomorrow

Wednesday, August 18, 2010

Recap of gummy bears experiment

In the quaint world of Ms. J's hands on experiments in fourth period, we ( 11 students :) ) continued our gummy bear labs. We measured them once more: height, length,width, and mass. After we finished all the good stuff some of my peers and I ate their gummy bears. sn: they were not as tough as yesterday, they were more slimy and gross. My conclusion from this experiment is that when gummy bears sit in water they become less dense. To conclude our day 8 of chemistry we started our review sheets for our test on Friday.

Qualitative fact: I wear contacts and I hate math... :) but I'm becoming more comfortable with it in this class.

Maria :]

Review & Gummy Bears

Today students came in and checked out their now very swollen gummy bears. The bears easily doubled in size and were very squishy and slimy. Students practiced and excelled in various math skills in Math Challenge Number One. In third period, Morgan and Tessa got perfect scores. In fourth period, April, Sam, and Josh got perfect scores. Students finished class by working on a review sheet to prepare for their Unit 1 Test on Friday.

Homework tonight - finish review sheets
Gummy Bear Lab and Unit 1 Packets due Friday
Unit 1 Test Friday

Tuesday, August 17, 2010

Gummy Bears 1 - by Sam (4)

Today in chemistry, we got to drown gummy bears. It was fun, Then we had to do boring notes about significant digits (sig digs) and the scientific method, which completed our notes fully. After finally finishing notes, we got some more sig dig and rounding practice. Finally, after one hour, we got to see how much our gummy bears grew or shrunk and we had to eat the slimy things.

Significant Digits

Today students started a lab involving the scientific method and measuring gummy bears. The students got their bears and measured them and then covered them in water to wait. While waiting students reviewed and practiced significant digits and went over the scientific method and related it to the gummy bear lab.

While we were working, the bears absorbed water and expanded in size. They get bigger and gooey-er and slimy and it's fun for me to watch. Everyone complains they can't eat the bears at the beginning, but complain they don't want to eat them at the end. The cool thing is - there is one more bear in the wings sitting for 24 hours... what is going to happen to it?

Homework tonight - Blue sheet boxes E and M
Rainbow Labs are Late
Gummy Bear Labs will be due Friday
Unit 1 Test on Friday - Packets due Friday

Monday, August 16, 2010

Scientific Notation and other math practice

Today students started class with an Accuracy and Precision Challenge. Students practiced with bullseyes, data, and calculated percent error. Too many people to name in third period got a perfect score, but only Katelin in fourth got a perfect. Congrats to everyone with a perfect score and good job to all participants.

We went over the homework from the weekend (B H I) and discussed our answers. We made sure everyone knew how to do the dimensional analysis math in box I and then did quite a few practice problems. Everyone knows how to do it, they only think they don't. Fourth period is particularly good at setting these problems up.

We discussed scientific notation and then did a few practice problems involving the multi-pli-cation of numbers in scientific notation.

Homework tonight - E and M
Rainbow Labs are due tomorrow.

Friday, August 13, 2010

Rainbow Lab

Today students began class by practicing percent error math problems (Box L on the homework sheet). They watched a BrainPop on scientific notation and took the quiz while a few students took, or re-took, the safety test. All Friday test-takers passed their safety tests.

The rest of class was spent on the first lab on accuracy and precision. Students worked with glassware and colored solutions. I watched them to see their maturity, safety, and ability to follow directions. If the lab is done correctly, precisely, and accurately, students get a row of test tubes with rainbow colors and they should all have the exact same amount of liquid.

Homework : Boxes B H I

Thursday, August 12, 2010

Measuring, Error, and Math

Today we started class with a BrainPop cartoon about precision and accuracy and then took the quiz. The quiz was harder than expected, but students did well.

We discussed percent error, a measure of accuracy. Students need to memorize the formula:

your value - accepted value         x 100%
        accepted value

Next we used the whiteboards and learned how to set up conversion problems. Once students felt comfortable, we did a little bit of notes and more practice problems. We will continue to practice dimensional analysis until the students have it down pat. I have plenty of practice problems. :)

Tonight's homework on the blue sheet is boxes A C D

Wednesday, August 11, 2010

Laboratory Equipment

After finishing up the safety test, students matched drawings of lab equipment with the proper names. We went over what this equipment looks like in real life (not a drawing) and discussed uses of the equipment.

We finished class with a discussion of accuracy and precision. Several volunteers helped by throwing squishy whales at a bulls-eye. With a bulls-eye, accuracy is hitting the target in the center. Precision is how close together the points are, whether they are accurate or not.

Tuesday, August 10, 2010

Chromatography and other chemistry techniques

Students started with a safety cartoon where they needed to identify what the people in the drawing were doing correctly and incorrectly. It was a contest and the winner had more than 50 points!

Next we discussed chromatography. Chromatography is used to separate inks into the colors that make them up. The reason it works is because the colors of ink have different size particles. The small particles move faster and will move further up the paper strip. Some black inks are actually made up of blue red, pink, and yellow.

We also discussed quantitative and qualitative observations. Qualitative observations are qualities and can be observed with the senses. Quantitative observations include numbers and are usually measuring something about an object. Toys were passed out for the students to practice with.

Monday, August 9, 2010

First Day of Class

Today was a get-to-know-you sort of day. Students started with an informal survey and drew a picture of themselves that I will use to help learn their names (I am terrible at names). I familiarized the students with classroom procedures, discussed homework and classwork, and let them know how class was going to run.

We went over the safety rules (test on Wednesday) by having the students draw a cartoon for a rule, and then having other students guess which rule was pictured. In 4th period, Nelly's drawing of how to handle sharp objects was voted the best with Caroline's figure in the correct lab safety gear was second. Third period will make their decisions tomorrow and I will post photos tomorrow as well.

Please read over the syllabus and safety rules and get those safety rules signed.

Tuesday, August 3, 2010

Welcome Back to School!

Greetings students, parents, and guardians.

Welcome to a new school year with Ms Jancaitis! This blog has been set up to connect students, parents, and guardians with the chemistry class.

At Open House or in class, each student will receive a course syllabus, safety rules, and a breakage sheet. The safety rules and breakage sheet needs to be read and signed by both the student and parent guardian.
  1. The course syllabus outlines what the course will be like, what topics will be covered, and course expectations. It also contains contact information.
  2. The safety rules are rules designed to keep the classroom safe and orderly to maximize learning and prevent accidents and injuries. These rules need to be studied because there will be a safety test on WEDNESDAY and infractions of these rules can lead to disciplinary action.
  3. A breakage sheet is a contract holding students accountable for the items that are broken if the student is acting a manner that is unsafe for themselves or those around them.
Please have these papers signed and returned by Friday. Students not returning signed safety rules and breakage sheets will not be able to participate in labs and activities until the contracts are signed and returned.