Thermochemistry

Today we’ll be covering the last topic of unit 2, Thermochemistry. Yes, it is exactly what it sounds like… Sort of. Thermochemistry may sound like its all about temperature, but really it’s more about the transfer of energy, specifically heat.
After today you will be able to calculate the amount energy (in the form of Calories or Joules) absorbed or lost when transferring energy, specifically heat. In order to do this, all you need to remember is a little song. Ahem…

“q” equals M-C-Delta t, M-C-Delta t. “q” equals M-C-Delta t, M-C-Delta t….

you get the point. The formula

q= m x C x /\t

is the formula for calculating transfer of energy.

  • q is heat calculated in Joules or Calories
  • m is the mass of the substance
  • C is the specific heat (the amount of energy, in Joules or calories, it takes to raise the temperature of 1g of substance 1 degree Celsius) of the substance
  • /\t is the change in temperature (t*final – t*initial)

The formula can be rearranged, like in math class, to get any of the variables alone to calculate one.

We’ll be starting some practice problems in class, then working on the rest tonight, and finishing up in class tomorrow before we start to review. The Answers can be found on the Semester 1 Docs Page.

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Prepare to start preparing for…

You guessed it! Your TEST IS THIS FRIDAY! Today you will be given a study guide to help you start organizing your thoughts and to start preparing yourself for the test. This test is usually a fairly easy test, but there is a lot of information… so start preparing now!

Before we’re ready to take the test we still have 2 topics to cover; 1 we’ve already sorta covered, and 1 brand new. Today we’ll be covering the one you already know a little something about, Substances & Mixtures. You’ll be using your book to answer some questions and do some inferring about what a substance and/or mixture is and how they are different. The handout and overview are located on the documents page (a filled in version will be available on the notes page tomorrow).

On top of that, today you’ll be given a study guide (available on the docs page) and a copy of tomorrow’s lab for you  to review.

Percent Composition

Today we’ll be using our Homework from last night (Molar Mass Worksheet) to determine the Percent Composition of different atoms in those molecules. It’s really easy see the example below to help you with today’s assignment. The Answer key can be found on the Docs page. Use this as a tool to check work, not to copy.

Molar Mass: CaCl2 %Composition: CaCl2
1 CaCl2 Molecule:
1 Ca  = 1 x 40.1 = 40.1
2 Cl
2 = 2 x 35.5 = 71.0
                            111.1g/mole
%Ca= (40.1/111.1) x 100 = 36.1%Ca
%Cl= (71.0/111.1) x 100 = 63.9%Cl

Molar Mass

No. Not that kind of molar. Moles refers to the amount of atoms in a substance… but we’ll save that for a later day. Today, we’ll be learning how to calculate the mass of a molecule based on the Atomic Weights of the Atoms within that molecule. There will be a Homework assignment associated with this activity that can be found on the documents page along with a complete periodic table.

BIG 44 QUIZ… and some other stuff that’s not as big.

Today’s the Big 44 Quiz. Make sure you can identify the symbols and/or spell the names of the 44 elements required. If you need a refresher on which 44 you need check the semester 1 Docs page.

After the quiz you’ll be receiving some info on Atoms, Molecules, and Compounds. This includes notes, some practice problems, and HOMEWORK! They can all be found on the same sheet so check out the Semester 1 Docs or Notes for the handout.

Ch-Ch-Ch-Changes…

Your To Do List:

  • Take the Pre Test (found using this link or the docs page)
  • Take the notes using voicethread (link found on notes page)
  • Take the Post Test
  • Create an illustration (Follow the directions below)
  • Study your flashcards

Today we’ll be learning about Physical and Chemical properties and changes. Today is an independent learning day because I will be out for part of the next two days as I am involved with a seminar here on campus. Therefore I’m putting the information in your hands with voicethread. The annotated notes (yes that means I’ll be talking) are available on the notes page. AND, due to popular demand, I’ve gone ahead and added the key questions to the PDF for you. I know, I know, I’m too kind. When you’re finished with the notes, I’d like you to follow these directions:

  1. Get a clean sheet of computer paper
  2. Fold the paper in half
  3. Write, in text big enough to read from 5 ft away, “Physical Change” on one side and “Chemical Change” on the other.
  4. Below the text, draw a picture of an example of that type of change that was NOT ILLUSTRATED IN THE NOTES.
  5. Below your picture, explain how you know this is the type of change that it is.
  6. Make it neat, clean, and colorful.
  7. Turn it in to the dropbox when you’re done.
  8. No Electronic posters this time.

Tomorrow you’ll be in the lab with Mr. Fogel or myself observing some of the changes discussed today. Tomorrow is also your BIG 44 QUIZ so study those flashcards!

Day of Service

Today the Cathedral family will be taking part in a day of service. Each county will be volunteering their time and efforts towards improving our community, aiding the less fortunate, and helping those in need. It’s important to remember to take time to give of ourselves, and today is a terrific opportunity to do just that. Although the work may be hard or tedious, it’s worth it. We have been given so many gifts, the least we can do is share them with the world.

Marshmallows are a Solid… right???

Marshmallows are a solid. But! they are also partially a gas, since their is air trapped inside the Marshmallow solid. That trapped air makes the marshmallow appear and feel “fluffy”. That being said, today you’ll be using mini-marshmallows to show me what you know about the 3 states of matter: Solid, Liquid, & Gas. Below is the directions on how to complete the activity and the template you need to fill in and turn in/email.

 

Marshmallow States of Matter

States Of Matter Template

If you need a refresher on the states of matter and how the atoms in each react with one another, see Chapter 2.1 in your iBook.

Mr. Kubuske will be available to answer questions as needed, but will be working on something very urgent from the U.S. Department of the Interior. More details to come later.