Congratulations on Completing Trimester 1 of Chemistry!

Week 11 Resources/ Assets
Updated November 8, 2018
Please make sure you READ everything on this page or you will miss important details. I will archive past weeks Announcements pages for a limited time only under the Trimester 1 and 2 tabs, if you need to go back to a particular weeks information for any reason.

Week 10 in Review

This last  week we started Chapter 7 - Chemical Quantities. Recollect it is broken down into the following sections:
  • Section 7.1 - The Mole: A Measurement of Matter
  • Section 7.2 - Mole-Mass and Mole-Volume Relationship
  • Section 7.3 - Percent Composition and Chemical Formulas
Hopefully you all remember what a mole is: it is a specific quantity (6.02 x 10^23) that describes how many particles (atoms, ions, formula units, molecules) are in a gram mass of a substance. As an example, one mole of carbon atoms (which has an atomic mass of 12.01 amu) contains 6.02 x 10^23 atoms, and weighs 12.01 grams. In class, we determined the gram mass of sucrose (C12H22O11) by calculating as follows:
  • ​12 carbons x 12.01 amu = 144.12 amu
  • 22 hydrogens x 1.01 amu = 22.22 amu
  • 11 oxygens x 16.0 amu = 176. amu
Making the total gram mass for one mole of sucrose equal to 342 g.
The concept of a mole enables scientists to "count" elements or compounds, by weighing them.

Looking Ahead to Week 11

On Tuesday, we will complete Chapter 7 by looking at mole-mass, and mole-volume relationships. Please feel free to read ahead and solve as many homework problems as you possibly can. Homework for Chapter 7 is not due until you return from Thanksgiving Break, November 27.

Finally, Chapter 7 will be completed learning how to calculate percent composition and empirical formulas. The percent composition of a compound, describes the relative amount (by mass) of each element within a compound. As an example, water, with a molar mass of 18.02 g/ mol, has a percent composition by mass of 11.2% hydrogen, and 88.8% oxygen. To calculate the percent composition of hydrogen in water, you divide the number of grams of the element H (2.02 g) by the gram molecular mass of water (18.02 g) =11.2%. Similarly, to calculate the percent composition of oxygen in water, you divide the number of grams of the element O (16.0) by the gram molecular mass of water (18.02 g) = 88.8%. We will go into more detail on this on Tuesday - please note that I have linked a Tyler Dewitt video covering this, at right - I encourage you to watch this. There is another helpful video  right below, explaining h ow to calculate empirical formulas.

On Tuesday, as a class we will carry out the lab, Small-Scale Lab - Measuring Mass as a Means of Counting. Please print out the lab (linked right) and bring with you to class on Tuesday.

If time permits, we will start Chapter 8 - Chemical Reactions. Chapter 8 is divided accordingly:
  • Section 8.1 - Describing Chemical Change
  • Section 8.2 - Types of Chemical Reactions
  • Section 8.3 - Reactions in Aqueous Solution

The five major classes of chemical reactions are:
  1. Combination (synthesis) reactions
  2. Decomposition Reactions
  3. Single-Replacement Reactions
  4. Double-Replacement Reactions
  5. Combustion Reactions

Chapter 8 is not quite as math-intense as Chapter 7, and I believe you will find it much more interesting, as we learn about these different types of chemical reactions.

Trimester 2 Schedule

I will have the Trimester 2 Schedule prepared before next Tuesday's classes. Please be reminded that what appears on the class webpage always takes priority over the published schedule.
So that you are adequately prepared for classes next week, please complete the following:
Tuesday, November 13th:
  1. ​Due in class: Test #2 - covering Chapters 5 and 6
  2. Due in class: Chapter 6 Homework.
  3. Feel free to watch the videos uploaded at right, covering Chapter 7 material.
  4. Print out Lab - Measuring Mass as a Means of Counting (linked below).