chemistry- summary and performance task
TRANSCRIPT
http://www.youtube.com/watch?v=98JuJ-G1qXY
Fireball
http://www.youtube.com/watch?v=-DjCum6yu8M Slow Mo- Flare
Summary of Chemistry Unit
Particle movement
Image source: http://www.chem.ufl.edu/~itl/2045/lectures/lec_f.html
GAME TIME!
You are a particle of water.The classroom is your beaker. And I control the temperature.
DO YOU KNOW YOUR CHEMICAL CHANGES?
REMEMBER the different signs of a chemical change:
1. 2.3.4.
Physical or Chemical?
Image source:http://irishenergynews.com/home/index.php/2010/12/03/what-fuel-to-use-part-1/
Physical or Chemical?
Image source: http://blog.emandco.com/choosing-a-perfume/
Physical or Chemical?
Image source: http://media.beta.photobucket.com/user/laquangela20/media/ist2_5404425-melting-ice-cream.jpg.html
Physical or Chemical?
Image source: http://www.campustimes.org/2011/03/24/fruit-on-campus-a-seriously-rotten-deal/
Chemistry Post-Test
What is ‘denaturing a protein’?
Denature: To change the natural qualities of something by chemical or physical means.
Protein: Proteins are fundamental components of all living cells and include many substances, such as enzymes, hormones, and antibodies, that are necessary for the proper functioning of an organism. They are essential in the diet of animals for the growth and repair of tissue and can be obtained from foods such as meat, fish, eggs, milk, and legumes. *
Why are we learning about denaturing a protein???
Performance Task Review *• What is our performance task for this unit on
transformations?• What do you think the type of transformation
is for denaturing? (Hint: what are the transformations we have learned about?)
• Why is this a ____________ reaction?
Video on Denaturing a Protein
• Some words and ideas you will need to know:– What are amino acids? – What is protein structure?– Why do we denature a protein?– What is coagulation? Can you give an example?
What are amino acids?Any of a large number of compounds found in living cells that contain carbon, oxygen, hydrogen, and nitrogen, and join together to form proteins. Twenty of the naturally occurring amino acids are the building blocks of proteins, which they form by being connected to each other in chains. Eight of those twenty, called essential amino acids, cannot be synthesized in the cells of humans and must be consumed as part of the diet. The remaining twelve are nonessential amino acids.
What is protein structure?
Coagulation
• To change or be changed from a liquid into a thickened mass: egg white coagulating when heated; blood clotting over the wound; gravy congealing as it cools; milk that had curdled; used pectin to jell the jam.
• From the FreeOnlineDictionary.com
Now we are ready to watch the video!
• http://www.youtube.com/watch?v=3IL_Df5ouUc (4 min)
• Watch first without taking notes, then we will watch again and take notes.
Another short video!
• http://www.youtube.com/watch?v=o2ju5ys3Cxc (35 sec egg)
DAY 2: Lab Demo (Denaturing Proteins) Intro to Performance Task
1. Make a hypothesis.2. Perform test.3. Record observations.4. Write summary statement.
1. Study procedure.2. Perform Lab 1: Making Jell-O3. Label cup (with Jell-O). Place in refrigerator.
Lab Demo: Denaturing proteins
1) Add hydrogen peroxide to fresh liver & make observations.
2) Do same for cooked liver.
• Initial observations and predictions (what do you expect to happen – make a hypothesis and describe the set up of your experiment – what are you going to do)
• Describe and Compare your observations.• Analysis: Explain if denaturation of the protein in liver occurred
and if so, how do you know?
BONUS Questions!
• What is the temperature at which denaturation occurs (from video clip)?
• Is denaturation reversible?
• What is happening when we heat a protein and how is this similar to the experiment we did on phase change of water? How is it different?
40° C
Sources
• http://www.thefoodadvicecentre.co.uk/reference/protein/
• www.thefreedictionary.com• http://www.elmhurst.edu/~chm/
vchembook/568denaturation.html
http://www.nbclearn.com/portal/site/learn/chemistry-now/cheeseburger-chemistry
Chemistry of Cheese Burger
PERFORMANCE TASK
“The Perfect Breakfast”Goal: Your goal is to manipulate properties of matter in order to prepare the perfect breakfast AND explain what you did.
Description: You are a “scientific” chef and you arein a cooking competition with a science twist. Your objective is to create a delicious meal while identifying and explaining all the chemical and physical changes during the cooking process. Your “cooking” will be evaluated by a panel of judges with little or no background in cooking but a lot of expertise in physical and chemical changes.
Judging Criteria: Your ability to identify, provide evidence for, and explain the physical and chemical changes that occurred during the preparation of the various parts of the meal.
You will be given the time and laboratory equipment to prepare each of these items, but, more importantly, you should look at the performance task questions and be able to answer them as you go along.
Specific Instructions: The Vitamin Tablet
1. Pour 100 ml of water into a Styrofoam cup. 2. Place a thermometer into the cup and record the temperature. 3. Take the mass of the water/Styrofoam cup, and thermometer system with
the un-dissolved tablet, by placing all of these items on the platform/digital balance.
4. After you have done all of these, place the tablet into the Styrofoam cup. Measure the reaction time. Measure the mass of the system after the reaction.
5. Now, observe and record your observations. Calculate rate of temp. change.
40 ml)
40 ml)
•The Bacon
1. Take a single strip of bacon and place it into a beaker. 2. Take the mass of the entire system. Also, measure the temperature.3. Cook the bacon and record your observations. 4. After the bacon is cooked, let the beaker cool and take the mass of the
system again. Record your observations. Note any change in mass. 5. Place a thermometer into the bacon grease. Observe and record your
observations.
