Week 2 has now gone up in flames... on to Week 3!
Week 3 Resources/ Assets
Updated September 7, 2018
This is your landing page for announcements and current news for your chemistry class. Please check this page often.
Physical and Chemical Properties of Matter
This last week through reading, class lecture, and homework questions, you should have learned that all matter has both physical and chemical properties. Recollect that physical properties are those we can readily measure or readily observe, such as:
Lab 2 - Separation of a Mixture
When chemists are tasked with the problem of identifying chemicals within an unknown mixture (such as a contamination spill in a lake), they take advantage of the differing physical properties of the chemicals within the mixture (if indeed the contamination released many chemicals) in order to separate them from one another. In the same way, we will do this next week when we separate a mixture of pebbles, sand, and salt by taking advantage of their differing physical properties.
Extra, Extra... Read all About it!
I didn't really get the chance to cover the last section of Chapter 2 - Section 2.4 - Chemical Reactions. Please make sure you read this section and understand it. The concept of great interest here is the Law of Conservation of Mass. Simply put: in any chemical reaction, mass is neither created or destroyed, but is conserved. If 16 grams of oxygen gas reacts with 2 grams of hydrogen gas, you will obtain as a result, 18 grams of water. The total amount of mass in the reactants always equals the total amount of mass in the products.
Looking Ahead to Week 3/ Chapter 3
For Chapter 3, the focus will now turn to measurement: how we accurately measure and record chemical information. I will not spend any time in class at all on how to deal with scientific (exponential) notation - this is a skill you should have acquired in pre-Algebra classes, but if you need a quick review on how to manipulate and write numbers in scientific notation, I have attached several links to Tyler Dewitt YouTube videos at right. Refer to these only if you need to. Finally, you should make sure this week that you know how to key exponents in your calculator.
We will spend quite a bit of time during the next few weeks on topics related to error. Unfortunately, error is a part of any measurement we make, so we have to learn how to record data values reflecting these errors, or at the very least reflecting the limitations of our measuring devices, whether they be rulers, graduated cylinders, or scales. This is where significant figures comes into play. When you return on Tuesday, we will perform the Separation of a Mixture lab, along with the Significant Figures lab.
Finally, if you think you would learn better by watching a video lesson on significant figures rather than reading in the textbook, please take advantage of the other Tyler Dewitt videos at the right. Watch these only if you want to.
So, young chemists, please make sure you do the following by:
Tuesday's class - September 11th
Scientific Notation videos by Tyler DeWitt (optional)
Significant Figures videos by Tyler Dewitt (optional)