Showing posts with label Carrie R.. Show all posts
Showing posts with label Carrie R.. Show all posts

Friday, November 22, 2013

11/22

review yesterday: When reaction occurs, the pressure changes to create equilibrium with the atmosphere.


Regular buildings don't affect atmospheric pressure.

We talked about laws of gases and changes in pressure that are regulated in certain buildings or underground caves and how pressure differences can be used to contain viruses in the CDC building.

Stoichiometry:
Volume of a gas under 2 sets of conditions, non-standard temperature and non standard pressure

Here are some examples, these problems can be found in the Unit 5 handouts folder, here’s how to set up the equations if you don’t understand it.
Ammonia is NH3, our “B” chemical, 6NO is our “A” chemical, however there is a typo in the question, there is no indication of pressure or temperature, so we assume STP and -273 degrees kelvin.

Start by writing 12 L NO, turn it into moles by using volume, 1 mol NO/ 22.4L NO.

12 L NO x(1 mol NO/22.4 L NO) x (4 mol NH3/6 mol NO) x (22.4 L NH3/1 mol NH3)

12 x 4 / 6 = 8 L NH3



102 g H2S x (1 mol/34.09 g H2S) x (3 mol O2/2 mol H2S) x (22.4 L O2/1 mol O2) =
100.5 ->101 L O2



12 g H2O2 x (1 mol H2O2 / 34.02 g H2O2) x (1 Mol O2 / 2mol H2O2) = 0.18 mol O2 -> PV=nRT
746 mmHg x V = 0.10 mol O2 x 62.4 (Lx mmHg/mol x K) x 300 K
V= 4.5 L

REMEMBER: You can treat volume like moles when its at standard pressure.

At the end of class today we did a demo about pressure how marshmallow and shaving cream expand in in volume when pressure is decreased and shrivel when pressure increases.

DONT FORGET TO DO YOUR PACKET THIS WEEKEND AND STUDY

Monday, October 21, 2013

10/21/2013

Today in class we went over homework Worksheet #4, found in the unit handouts on moodle.
Also we turned in the lab, although it's alright to take one more day to correct it and turn it in tomorrow 10/22/13.


The countdown Begins:

 UNTIL MOLE DAY!!!

AND THE...

Check moodle for homework and finish the quiz we started in class today, don't forget to get help from your partners! And don't forget to do your review packet.


Wednesday, September 4, 2013

Class Blog 9/4/2013

Questions for today, 9/4/2013


-What the heck is this dimensional analysis this all about? Why should i care?
-What is the best way to prepare for a chem quiz?
-Practice, practice, practice


Conversions

Use conversion factors to turn one unit into another that’s unit can’t be changed correctly by simply moving a decimal.

We did much practice of this in class going over how to convert units on a handout worksheet for practice that can be found on the moodle page under "Unit 1 Handouts". If you missed today's lesson, or aren't still 100% sure on how to convert units, here's a link to a helpful video.
http://www.youtube.com/watch?v=w0nqd_HXHPQ&list=HL1378352416



Significant Figures Reminder:



Stations

ruler_10_20.jpg (1182×403)At the end of class today, we did a short activity to review how to correctly measure units with the lab equipment including a buret, beakers, a graduated cylinder, ruler and thermometer.

Review List to Know

1. Chemical vs. Physical changes
2. Particular Nature of Matter (1.1)
3. Paperclip lab
4. Lab safety
5. Observation vs. Inference
6. King Henry Doesn't Use Dusty Crusty Mustard
     -K H D U d c m
7. metric conversions
8. temperature conversions- kelvin, celcius, fahrenheit 

 Quick Review:

1. Chemical Changes = Identity Changes  ;   Physical Changes = Identity Stays the Same
2. Define "matter" [in it's 3 forms (s) (l) (g)], "pure substance", "mixture" (heterogeneous and homogeneous), "element", and "compound".
3. Look over lab
4. Look at notes
5. Observation is something that can be seen vs. Inference, which is just an educated guess
6. Know order or Kilo Hecto Deka [UNIT] deci centi milli
7. move the decimal
8. look at unit conversions for temperature

Example Results for the Measurement Activity Done in Class


REMEMBER: QUIZ ON FRIDAY!!!!

              Don't forget to check Moodle for the homework!

Our Next Scribe will be...

Kate Maki!