Today we’re going to begin studying Gas Laws… (and that doesn’t mean the rules on Dutch Oven or letting one go in a crowded elevator).

We’re going to try some new classroom techniques for this final unit and create an “Open” classroom. Below are the expectations of you the student and of me the teacher.

Student Values:

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Yesterday, we started a lab with Cu/Fe. As a part of that lab, we’ll need to calculate how many moles of Cu/Fe were produced using the amount of grams of each. But what the heck is a Mole?

Moles are a unit of measurement, sort of like “a dozen”. The term “dozen” refers to 12 of any item. A “mole” is sort of the same. Moles are equal to 6.02 x 10²³ atoms. Thats 602,000,000,000,000,000,000,000… a lot of atoms. The real purpose of the ‘mole’ is to be able to do calculations of certain types of atoms, or between certain types of atoms. For example…

To calculate grams from moles we use the FACTOR LABEL method. Let me show you what I mean…

Lets say you weighed your sample and have 105.5 g Cu atoms (Its important to label your values this way for future use; we’ll always add the element and “atoms” after the unit) and we want to know how many moles that is. well what do we know…

105.5 g Cu atoms   ->   ??? mol g Cu atoms

Well… lets think about this. Do we know how many grams are in 1 mol Cu atoms so we have something to compare this to??? Let’s look at our handy-dandy periodic table; find Cu; the atomic mass listed there is equal to the weight of 1 mol Cu atoms!

1 mol Cu atoms
63.5 g Cu atoms

So lets put this value into our formula and see if we can make this work…

105.5 g Cu atoms   x  1 mol Cu atoms
1                                  63.5 g Cu atoms

We can cross out the “g Cu Atoms” units so the only unit remaining is “mol Cu atoms“. So…

105.5 x 1 mol Cu atoms       = 1.66 mol Cu atoms
63.5

___________Easy! When you go from grams to moles you DIVIDE BY THE ATOMIC MASS!_______________
But, what if I want to go from moles to grams??? EASY!!! MULTIPLY BY THE ATOMIC MASS!
What is the weight of 2.5 moles of Carbon atoms?

2.5 mol C atoms x 12.0 g C atoms  =  30.o g C atoms
1                           1 mol C atoms

Since, 1 mole of any element = atomic weight of that element, you can flip the equation to work for you! Since we have moles on the top left of the formula, we want moles on the bottom right so they can cancel out!

Now you can do the Grams to Moles Conversions Worksheet (found on semester 1 Docs).

Today we’re going to begin studying Gas Laws… (and that doesn’t mean the rules on Dutch Oven or letting one go in a crowded elevator).

We’re going to try some new classroom techniques for this final unit and create an “Open” classroom. Below are the expectations of you the student and of me the teacher.

Student Values:

1. You are encouraged to collaborate (share) ideas, information, and how to complete problems with fellow classmates. This means sharing information, not giving answers. The point of collaboration is to better understand the material ourselves and be of service to a colleague. The only thing you may not share are the puzzle pieces; they must be received individually and documented by the instructor.
2. If you are sharing a resource digitally on the blog or Google Doc you should use your first initial and last name to identify you. Posing as another student is considered fraudulent and does not follow the mission of the school. Any student posing as a colleague will face loss of points and other possible disciplinary actions.
3. You are tasked with completing 10 topics before you are permitted to attempt the final test. For each topic you complete, you will receive a piece of the puzzle that you are literally and figuratively completing during this unit. You may work at your own pace provided you meet the deadlines set by the teacher.
4. Since you will be permitted to use the internet and technology as you see fit, you may come across material that is inappropriate for a high school. When this occurs, close your iPad and raise your hand. Do not draw attention to yourself or share the text or images with others.
5. You are permitted to move about the room as needed to complete tasks and collaborate with colleagues. But in a working environment you must respect the workspace and work ethics of those colleagues by not becoming a distraction.

Failure to follow these values will result in a deduction of points from your Unit 10 score.

Gas Laws Puzzle .pdf (Download to Noteability)

Teacher Values:

1. Be of service to my students by providing a framework digitally and within the classroom to allow for free flow of ideas and learning.
2. Provide guiding questions to show students direction they should look to complete their sections.
3. Be available for mentoring and guidance through challenging material.

As you complete each section you will be asked a set of questions to prove your knowledge of the subject. You must score a 100% to receive your piece of the puzzle then move on to the next section. You are permitted to attempt these questions as many times as needed to receive a score of 100%. You will only lose points by failing to follow the values listed above. You can receive extra consideration for extra points or returning lost points by helping fellow students or providing useful sources for fellow students.

Now that you have completed the simple VSEPR diagrams and made your models of Linear, Trigonal, and Tetrahedral molecular geometry… it’s time to break the rules.

The rule we’re breaking is the Octet rule. To this point you have limited the central atom to sharing up to 8 electrons. But, If your Lewis Dot Diagram has too few electrons, you add pairs of electrons to the central atom.

Let me show you what I mean. Let’s say that we have XeF₂.If you calculate the valence electrons you should have 22.
But when you make the Lewis Dot Diagram, it only has 20 ve^–.

So, we add a pair of electrons to the Xe central atom giving us a total of 22 ve^–This creates a new Ideal Geometry known as Triangular Bipyramidal, which means it has placement for 5 parts (attached atoms or free electron pairs) around the central atom.

Like Tetrahedrons, we are working now in 3-dimensions instead of 2.

There is also an Ideal Geometry for 6 parts known as Octahedron. Think of the central atom as a 6 -sided die. So atoms can be bonded in 6 places and in 3-dimensions!