Q3 – Week 3 – 19-20
week 3
Week of 2/10 – 2/14
2/10 – Monday – period 7 – Academic Study Hall
-period 8
1. electron configuration review based on energy levels:
 |
Electrons that are core are closer to the nucleus = STABLE = low energy shells
These electrons “feel” the nucleus more because they ARE CLOSER to the positive protons in the nucleus that attract the oppositely charged negative electrons. (Like charges repel).
Electrons that are valence are farther away from nucleus = Unstable = high energy shell
These electrons “feel” the nucleus less because they ARE FARTHER to the positive protons in the nucleus that attract the oppositely charged negative electrons. (Like charges repel).
2. photo electric effect – Light as a particle = photon = discreet amount of energy.
3: spectrophotometry activity – The spectrophotometer shoots a white light (full spectrum of all photons) through the sample in the cuvette. The detector measures what is missing. Missing photons are absorbed (electrons transition away from the nucleus) by the pigment and the amount of missing photons or absorbed photons is measured by the height of the peak.
3. bright line Spectrum
4. Absorption spectrum
Yellow pigments = Blue/violet photons are absorbed = missing
Violet/Indigo/Blue photons absorbed = peaks
BLUE Pigments = red and yellow are absorbed = missing
Mostly yellow and red photons absorbed = peaks
green pigments = Blue and red photons are absorbed = missing
Blue and Red photons absorbed = peaks
Why are plants mostly green?
Todays Demo (If there was not an epic fail!):
I tried this afternoon but it did not work as well as the video above (last year).
I tried another version this year:
2/10 – Monday Homework:
1. Please view and read through the presentation below (slides 24 – till the end).
2. Watch the 2 video’s on the early atmosphere of the earth
3. Complete the True and False form on the presentation
photoelectric effect animation:
End Monday!
2/11 – Tuesday – period 7
We learned that elements like to ABSORB photons of light (energy) when electrons get excited and move away from the nucleus. They are now unstable and return to their low energy positions closer to the positive nucleus and give off the same light that they absorbed.
We looked ay bright line spectra from several elements and compounds. In particular we looked at hydrogens bright line spectrum ti identify its famous red line that represents an electron returning to the 2nd shell from the 3rd. We used diffracting lens to see the bright lines.
We played the animation (the thing at the bottom of today with circles). Please play if you can to understand where the bright line come from. Also look through the presentation, Light theories and the plant posted Monday above.
To get a feel of bright line spectra view my video below:
We then began the Photosynthesis lab by performing chromatography to separate the pigments of the spinach leaves that are in the photosystems. Please look through the presentation that explains the lab (photosynthesis lab).
1: Bohr transitions Flash link in presentation
2: Photosynthesis Lab part A:
Separating the pigments in the photosystem II an I
Chromatography/spectrophotometry
*USE Chromatography solvent 9:1 (90% Petroleum Ether, 10% actetone) WARDS
Photosynthesis pigments Lab – complete data collection
Chromatography Demo:
Energy Transitions in the Hydrogen atom: (flash)
Part 1 – Chromatography, separation of the pigments, and identification.
Todays Data From Class Today:
I am posting 2 images form your spectrophotometer today. The first one has your data with each pigment separated. The second one that I ran on your spectrophotometer with spinach leaves that you left on the table soaked with the solvent. This represents ALL the pigments collectively and should look similar to the image with the pigments separated. This should be discussed.
Please use both graphs in your data section.
Please click on your images to download
Morgan2 and Christie
Jack, Kristina, Gavin, Kade
Maximus and Daniel
Edgar and Evan:
Theresa and Emma Photosynthesis Lab:
2/11 – Tuesday Homework:
1: Please resubmit the Light and the Plant Form.
2: Please begin the slide -up of the Plant pigments from google doc that I sent you.
**Get a good start on this!! IT is not expected to be done by tomorrow.
*Remember the purpose to identify the pigments in the photosystems that help capture photons of light from the sun to excite electrons to higher energy states. Use you lab packet to help.
You must have the following:
You are to do this in Google Slides like we did for the Sordari Firmicola Lab EXCEPT everone will be doing their own slide up.
1. Title Slide
2. Background slide(s) – Do no make these slide all words or all pictures. Use this presentation
format to use more visuals but with explanations. Be creative, using the
concepts of the scientific method.
3. Objectives, Question, and Hypothesis – There is no real hypothesis in this lab.
There are important objectives:
1. Identify as many of the pigments in the photosystems are possible. The major players are
Carotene –
Xanthophyll –
Chlorophyll a –
Chlorophyll b –
a) You will Separate and identify the pigments in the spinach.
You will need to identify each band in the chromatograph by their
particular absorption spectrum, that when added together looks like the Total
Pigments absorption spectrum that we did earlier in the week (in slide 9 ) of my
presentation.
b) Using the Appendix A in your lab OR ANY OTHER RESOURCES and your lab file posted below you can
identify the pigment that was isolated in each band, based on absorption peaks.
2. Procedure – comprehensive list of steps so that anyone can follow.
3. Materials-
4. Data – Graphs from the logger pro files that are posted above WITH YOUR pictures of YOUR chromatograph.
I want to see you identify each line on the image posted above for each pigment you separated.
Please use the lab packet given out or the internet to find graphs from spectrophotometers to help
identify each pigment.
5. Results –
6. Conclusion – Do not be vague but to the point.
Explain your results. Make a leap. Fully explain any errors or limitations of the lab.
7. SOURCES
End of Tuesday..
2/12 – Wednesday – period 7 – Academic Study Hall
period 8
I explained in detail what we accomplished in yesterday’s Pigment lab. I also explained how and why we gathered the data and what should be in the conclusion for the lab. Slides 1 – 11 in the photosynthesis presentation posted below. This lab is a slide-up.
I then reviewed the procedure of tomorrows lab which is on the factors that affect the was the rate of photosynthesis. Have we done a rate of reaction lab before?
We tried to gather some control data which was unsuccessful.
1. Work on the slide up of the Photosynthesis Pigment Lab
1: photosynthesis Lab –
Part 1 – Chromatography, separation of the pigments, and identification.
– review of what we did and what is expected
2/12 – Wednesday – Homework
1. Please continue working on the Pigment lab.
2. Ecology Form 1:
2: Ecology – I was planning to give you a lot of homework over the winter break. During this time I was going to give you 4 forms that review all the basics of Ecology that you need to learn. I just do not have time to teach these very easy concepts so please do these forms with your book.
The total four forms will be due after Winter Break but if you want to get a head start please use your extra time to get ahead.
All four Ecology Forms will be due Tuesday February 26 at 7:30 am.
Ecology Forms 1:
End of Wednesday..
2/13 – Thursday – period 7/8 – Lab
1. The Rate of Photosynthesis Lab begins
a) gathered control data
DO NOT USE SOAP SOLUTION TO SINK THE disks!!!
Use the .2 % solution ( 2 grams in 1000 ml of water).
2. began thinking about what independent variables you want to test.
2/13 – Thursday Homework:
1: Continue working on the slide-up of the Pigment Activity. Your conclusion should include the identification of the pigments. The slide- up is due Friday 2/14.
2: Ecology Form 2:
Ecology Form 2:
End Thursday.
2/14- Friday – period 6/7
DO NOT USE SOAP SOLUTION TO SINK THE disks!!!
Use the .2 % solution ( 2 grams in 1000 ml of water).
1. The Rate of Photosynthesis Lab continues..
*Do not use any soap!!!
*Also use syringes medium to small to sink spinach disks. Stay away from vacuum
chamber.
a) Create a Plan of your unique study.
b) ET 50 explanation
c) start gathering data for guided inquiry lab
Also I tested the cellophane filters and the following light traveled through each of the filters.
Here are the pictures of the wavelengths of the light that traveled through the films:
It appears that the cellophane filters did filter some the light but it did reemit the color of the cellophane.
Complete spectrum: No filters
Clear cellophane: Some light from light bulb is filtered.
Blue cellophane: A lot of red is filtered out but a lot of Blue is emitted.
Green Filter: Some blue is filtered and some red is but green is emitted.
Red Filter: A lot of greens are filtered but a lot of red is emitted.
2/14 – Friday – Homework:
Optional – get a start on the Ecology forms. The third one is posted below. All four are posted in its own page in quarter 3.
1. Ecology 3 (of 4 Form):
End week 3!