Notes on Notes

Happy Tuesday Everyone!

Today, we took the allll the notes we neglected to take on Friday or Monday. The topics were collision theory, reaction mechanisms, reaction rate and factors affecting reaction rate. I give a short summary of each of them below, but you can find the real notes at http://GBS-Moodle.glenbrook225.org/moodle/mod/resource/view.php?id=86333

Collision Theory

When a reaction takes place, it is because molecules collide with each other at 1) the right speed and 2) the right orientation. The "activated complex" is this transition stage between reactants and products during a reaction. The "right speed" is otherwise none as the activation energy.

Reaction Mechanisms

A reaction does not happen all in one go; a series of steps makes a reaction happen. The "crash" happens, and then the old bonds break to form new bonds. The overall reaction, called the complex reaction, given on paper is just the end result, and many elementary or intermediate steps are taken to get there. 

Reaction Rate

This is a measure of how quickly the reactants in a reaction become products, or how much reactant is used over time. We will calculate this in units of molarity (mol/liter) per any unit of time (seconds, minutes, etc). The elementary steps of the reaction all have different required activation energies, and the step with the highest activation energy will take the longest to complete. This is called the rate-determining step, because it will be the factor that affects the speed of the reaction.

Factors Affecting Reaction Rate

Factors include: an increase in temperature, an increase in concentration (molarity), an increase in surface area, and the addition of a catalyst. A catalyst lowers the activation energy of certain slow elementary steps and can also provide different paths for a reaction to take, making it go faster.

Homework:

Check the answers to the equilibrium packet assigned yesterday (http://GBS-Moodle.glenbrook225.org/moodle/mod/resource/view.php?id=86334)

2 WebAssigns are due on Wednesday by 11:59 pm 

Kinetics and Equilibrium

Introduction to Kinetics and Equilibrium Unit

Friday, March 7, 2014

Today's chemistry class was all about the "It's Friday" spirit. It all started with Ms. Friedmann and Kevin G. balancing on the edge of the counter with one foot. This demonstrated holding an equilibrium…

Instead of taking notes, Mrs. Friedmann thought it would be a good idea to demonstrate some bigs ideas of this unit by doing activities in the old pit. These activities involved the class following directions:

• We tried the have a balance between two groups of people; this was done by having the same number of people on a side, making it symmetrical. 
• We tried having a group of 11 and 8 and had a flow of people traveling from one side to other other. The same number of people walking from one side maintained the balance of 11 and 8 and was not symmetrical.
• We tried having the two balanced groups of people, but everyone was moving in constant motion on each side. After walking in circles for a few moments, we had still maintained a balance.
• We tried having two groups where one group had two people walk over simultaneously with one person from the other group. This switch-up eventually led to one person on one side and the rest of the class on the other. This ended up not maintaining the balance because a different number of people from each side walked during each pass.

Lessons Learned:

• What comes in, must go out
• Equilibrium does not mean symmetrical
• Chemical reactions may appear as if doing nothing but is maintaining equilibrium
• Dynamic Equilibrium always moves, but is also always balanced

Next we went back into the class, so Mrs. Friedmann could bring fire. I left class 5 minutes early, so if anyone wants to recap what happened there in the comments, that'd be great.

Homework:

1. 2 crash course videos that you need to watch and take BIG-IDEA-ONLY notes where this should only take up 2/3 or 1 journal page for both videos 

• https://www.youtube.com/watch?v=7qOFtL3VEBc&feature=youtu.be
• https://www.youtube.com/watch?v=g5wNg_dKsYY&feature=youtu.be

1. Unlike the calendar, Mrs. Friedmann will NOT be having us do a web assign over this weekend, but will be assigned at a later date.

The next blogger is…Cool Chris