Micro Biology Lab Packet

Micro Biology Lab Packet. NAME: Section/Time:

Microbiology Lab Packet #2

Think of these lab packets as homework for the lab part of the class. They are designed to help prepare you for the departmental lab exams. To answer these questions you will need to use both the lab workbook as well as your text book. In addition to these questions, you will need to turn in the signed data sheets from your workbook.

19. Describe the molecular basis behind Gram staining. What part of the bacteria is stained with the primary stain, what part is stained with the counter stain? Why do we wash alcohol over the slide before the counter stain?

18. Describe in great detail the steps in performing a Gram stain. Include incubation times. Define primary stain and counter stain. In the Gram stain, what dye is primary stain, which is the counter stain?

 

Special Stains (Capsule Ex. 3.9, Endospore Ex. 3-10, Flagella Ex. 3.12)

21. What is the stain is shown in the picture below? What is stained green, what is stained red?

22. Describe in great detail the steps in performing an endospore stain. Include incubation times.

20. What does it mean to be Gram positive, Gram negative?

image1.jpg

23. Label the different flagellum arrangements seen below.

image2.jpg

24. Describe the negative staining technique and determine when it is used.

Colony Morphology Ex 2.2

25. We can learn some information about bacteria by just looking at its growth on an agar plate. What is a small isolated growth of bacteria on an agar plate called and what can it tell us about the bacteria?

Micro lab packet 2

Kirby-Bauer Method Ex 7.3

26. Describe in great detail the technique used to determine bacteria sensitivity to antibiotics?

27. What is the type of media used in the Kirby-Bauer test and why is it used?

Describe what is observed for a bacteria that is sensitive to antibiotics in a Kirby-Bauer test, and to a bacteria that is not sensitive to antibiotics.

28. How does the antibiotic get from the disk into the agar?

Does the agar have an antibiotic beyond the zone of inhibition?

29. Define the MIC and explain how it is used to determine if a bacteria is resistant or sensitive to the antibiotic.

Is the presence of a clear zone around the disc enough evidence to determine antibiotic resistance?

Micro lab packet 2

Disinfectants Ex 2.14

30. Compare your results with the class data.

Which germicide was most effective and at what concentration?

Which was the least effective? Defend your choices.

31. Which organism seemed to be most resistant to the germicides?

32. What purpose did the four controls serve? Be specific.

 

Include Completed Data sheets for:

1. Data Sheet 3-7 (pages 201-202) Sketch & id whether Gram + or Gram – and Questions 1-2

2. Data Sheet 3-9 (pages 213-214) Sketch capsuled stained bacteria; Questions 1 & 2

3. Data Sheet 3-10 (pages 219-220) Sketch Endospore Stained bacteria; Questions 1-4

4. Data Sheet 3-12 (pages 227-228) Sketch Flagella Stained bacteria; Questions 1 & 3

5. Data Sheet 2-14 (pages 139-140) Questions 1-3

6. Data Sheet 7-3 (pages 535-536) Questions 1-7

Gram Staining 3.7

 

 

33. What is the difference between disinfectants and antiseptics?

Micro Biology Lab Packet

 
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Biology Research Paper

Biology Research Paper. BACKGROUND

During your study of biologr, you may have found a contro- versial topic you read about to be especially interesting. This assignment gives you an opportunity to apply what you’ve learned by doing some research in outside sources and increasing your knowledge of one controversial topic.

Procedure

Go to http: / /lessons.pennfoster.com I pdt I sp0754.pdf and read the instructions for research papers. Select a controversial topic from the following choices.

r Human stem cells

I Genetically modified foods

r Climate change

r Cloning

I Designer babies

Consult resources other than the course textbook and this study guide. Examples of resources include other textbooks, journal articles, and reputable websites. Reputable online sources include enryclopedias and universitSr or governmental websites. Prepare a detailed report on the topic, including the following elements:

1. Describe the basic issue of your chosen topic.

2. Describe the basic argument of opposing viewpoints.

3. Identiff the strengths and weaknesses of both views.

4. Choose which view you agree with. 5. Explain why you agree with that view.

Incorporate the information you learned about your chosen topic from this course, but don’t limit your discussion to the textbook and study guide. Take advantage of extemal resources to provide an in-depth, comprehensive report.

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Goal

This assignment is designed to help you apply what you’ve learned from your lessons by researching and writing about a controversial topic you’ve studied and to give you an oppor- tunity to demonstrate your written communication and research skills, as well as your critical thinking skills.

1.

2.

3.

4.

5.

6.

Writing Guidelines Tpe your submission, double-spaced, in a standard print font, size 12. Use a standard document format with l-inch margins. (Do not use any fancy or cursive fonts.)

Include the following information at the top of your paper:

a. Name and complete mailing address

b. Student number

c. Course title and number (lntroduction to Biologr, SCI 120)

d. Research project number (25088100)

Read the assignment carefully and address the topic suggested. Use proper citation in either APA or MLA style,

Be specific. Limit your submission to the topic suggested.

Include a reference page in APA style. On this page, list websites, journals, and all other references used in preparing the submission.

Proofread your work carefully. Check for correct spelling, grammar, punctuation, and capitalization.

Research Project

Grading Criteria

Your grade will be based on the following criteria:

Content 75 percent Written comrnrrnication 20 percent Format 5 percent Here’s a brief explanation of each of these points.

Gontent

The student

I Describes the basic issue of his or her chosen topic

r Describes the basic argument of opposing viewpoints

r Identifies strengtJrs and weaknesses of both the pro and the con views

t Chooses a view with which he or she agrees

r Explains why he or she agreed with the chosen view

Written Communication

The student

r Uses correct grammar, spelling, punctuation, and sentence structure

r Stays focused on the assignment

I Includes an introductory paragraph, a body with well- defined paragraphs, and a clear conclusion

I Uses his or her own words and uses quotations and citation in the form of a reference page correcfly

Format

The student includes a cover page with the following information.

r The title in capital letters

I Name and student number

I Current date

I Course title and number (Introduction to Biologr, SCI 120)

I Research project number (25088100)

Student uses standard 12-point font and l”-inch margins.

Submittlng Your ProJect

Follow this procedure to submit your project online:

1. Log on to the Penn Foster website and go to My Courses.

2. Click Take Exam next to the lesson you’re working on.

3. Attach your file as follows:

a. Click on the Browse box.

b. Locate the file you wish to attach.

c. Double*click on the file.

d. Click Upload Flle,

3. Enter your e-mail address in the box provided. (Note: This information is required for online submissions-)

4. If you wish to tell your instructor anything specific regarding this assignment, enter it in the Message box.

6. Click Submlt File.

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l!;ia;.4?.?t:,: Research Project

 

Biology Research Paper

 
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Assessing The Heart, Lungs, And Peripheral Vascular System

Assessing The Heart, Lungs, And Peripheral Vascular System. Make a SOAP Note: Assessing the Heart, Lungs, and Peripheral Vascular System

Scenario 2

Vital signs:

Temperature: 97.9 oral

Respiratory rate: 32, labored

Heart rate: 112, tachycardic

BP right arm: 148/88

Oxygen saturation: 90% on room air

Weight: 210 lbs, stable

Skin: Cool, diaphoretic

Thorax and lungs: Thorax symmetrical; diminished breath sounds right middle and lower lobes; no rales, rhonchi, or wheezes; breath sounds vesicular with no adventitious sounds left lung

Cardiovascular: Heart rate is irregular with good S1, S2; no S3 or S4; no murmur

Abdomen: Protuberant with normoactive bowel sounds auscultated x4 quadrants

Peripheral vascular: Right calf with 2+ edema, erythema; warmth and tenderness on palpation noted; left lower extremity without edema or erythema; 2+ dorsalis pedis pulses bilaterally

——————————————————————————————————————————-

Instructions: Your Discussion post should be in the SOAP Note format, rather than the traditional narrative style Discussion posting format. Refer to the Comprehensive SOAP Template/Exemplar on the attachments below.

Address all these in the SOAP Note:

1. A description of the health history you would need to collect from the patient in the case study 2.

2. Explain what physical exams and diagnostic tests would be appropriate and how the results would be used to make a diagnosis.

3. List five different possible conditions for the patient’s differential diagnosis, and justify why you selected each.

REMINDER: Please make a SOAP NOTE for this case. Make your own patient’s data, applicable health history, review of systems, P.E., labs, etc. Incorporate the data from the case 2 in the SOAP note that you will do… This is not essay ok…. I need SOAP note (Nurse Practitioner/RN/MD makes SOAP note)… Be guided with the templates/exemplar… Don’t copy paste. Formulate your own… Don’t forget to cite the Five different possible conditions (Differential diagnosis) and have Reference lists too.

RESOURCES:

Readings

· Ball, J. W., Dains, J. E., Flynn, J. A., Solomon, B. S., & Stewart, R. W. (2015). Seidel’s guide to physical examination (8th ed.). St. Louis, MO: Elsevier Mosby.

o Chapter 13, “Chest and Lungs” (pp. 260-293)

This chapter explains the physical exam process for the chest and lungs. The authors also include descriptions of common abnormalities in the chest and lungs.

o Chapter 14, “Heart” (pp. 294-331)

The authors of this chapter explain the structure and function of the heart. The text also describes the steps used to conduct an exam of the heart.

o Chapter 15, “Blood Vessels” (pp. 332-349)

This chapter describes how to properly conduct a physical examination of the blood vessels. The chapter also supplies descriptions of common heart disorders.

· Dains, J. E., Baumann, L. C., & Scheibel, P. (2016). Advanced health assessment and clinical diagnosis in primary care (5th ed.). St. Louis, MO: Elsevier Mosby.

o Chapter 8, “Chest Pain” (pp. 81–96)

This chapter focuses on diagnosing the cause of chest pain and highlights the importance of first determining whether the patient is in a life-threatening condition. It includes questions that can help pinpoint the type and severity of pain and then describes how to perform a physical examination. Finally, the authors outline potential laboratory and diagnostic studies.

o Chapter 11, “Cough” (pp. 118-147)

A cough is a very common symptom in patients and usually indicates a minor health problem. This chapter focuses on how to determine the cause of the cough through asking questions and performing a physical exam.

o Chapter 14, “Dyspnea” (pp. 159–173)

The focus of this chapter is dyspnea, or shortness of breath. The chapter includes strategies for determining the cause of the problem through evaluation of the patient’s history, through physical examination, and through additional laboratory and diagnostic tests.

o Chapter 26, “Palpitations” (pp. 310-317)

This chapter describes the different causes of heart palpitations and details how the specific cause in a patient can be determined.

o Chapter 33, “Syncope” (pp. 390-397)

This chapter focuses on syncope, or loss of consciousness. The authors describe the difficulty of ascertaining the cause, because the patient is usually seen after the loss of consciousness has happened. The chapter includes information on potential causes and the symptoms of each.

· Sullivan , D. D. (2012). Guide to clinical documentation (2nd ed.). Philadelphia, PA: F. A. Davis.

o Chapter 6, “Outpatient Charting and Communications” (pp. 119–141)

Note: Download these Adult Examination Checklists and Physical Exam Summaries to use during your practice cardiac and respiratory examination.

· Seidel, H. M., Ball, J. W., Dains, J. E., Flynn, J. A., Solomon, B. S., & Stewart, R. W. (2011). Physical exam summary: Blood vessels. In Mosby’s guide to physical examination (7th ed.). St. Louis, MO: Elsevier Mosby.
This Blood Vessels Physical Exam Summary was published as a companion to Seidel’s guide to physical examination (8th ed.), by Ball, J. W., Dains, J. E., & Flynn, J. A. Copyright Elsevier (2015). From https://evolve.elsevier.com/

· Seidel, H. M., Ball, J. W., Dains, J. E., Flynn, J. A., Solomon, B. S., & Stewart, R. W. (2011). Adult examination checklist: Guide for cardiovascular assessment. In Mosby’s guide to physical examination(7th ed.). St. Louis, MO: Elsevier Mosby.
This Adult Examination Checklist: Guide for Cardiovascular Assessment was published as a companion to Seidel’s guide to physical examination (8th ed.), by Ball, J. W., Dains, J. E., & Flynn, J. A. Copyright Elsevier (2015). From https://evolve.elsevier.com/

· Seidel, H. M., Ball, J. W., Dains, J. E., Flynn, J. A., Solomon, B. S., & Stewart, R. W. (2011). Adult examination checklist: Guide for chest and lung assessment. In Mosby’s guide to physical examination (7th ed.). St. Louis, MO: Elsevier Mosby.
This Adult Examination Checklist: Guide for Chest and Lung Assessment was published as a companion to Seidel’s guide to physical examination (8th ed.), by Ball, J. W., Dains, J. E., & Flynn, J. A. Copyright Elsevier (2015). From https://evolve.elsevier.com/

· Seidel, H. M., Ball, J. W., Dains, J. E., Flynn, J. A., Solomon, B. S., & Stewart, R. W. (2011). Physical exam summary: Chest and lungs. In Mosby’s guide to physical examination (7th ed.). St. Louis, MO: Elsevier Mosby.
This Chest and Lungs Physical Exam Summary was published as a companion to Seidel’s guide to physical examination (8th ed.), by Ball, J. W., Dains, J. E., & Flynn, J. A. Copyright Elsevier (2015). From https://evolve.elsevier.com/

· Seidel, H. M., Ball, J. W., Dains, J. E., Flynn, J. A., Solomon, B. S., & Stewart, R. W. (2011). Physical exam summary: Heart. In Mosby’s guide to physical examination (7th ed.). St. Louis, MO: Elsevier Mosby.
This Heart Physical Exam Summary was published as a companion to Seidel’s guide to physical examination (8th ed.), by Ball, J. W., Dains, J. E., & Flynn, J. A. Copyright Elsevier (2015). From https://evolve.elsevier.com/

· McCabe, C., & Wiggins, J. (2010a). Differential diagnosis of respiratory disease part 1. Practice Nurse,40(1), 35–41.
Retrieved from the Walden Library databases.

This article describes the warning signs of impending deterioration of the respiratory system. The authors also explain the features of common respiratory conditions.

· McCabe, C., & Wiggins, J. (2010b). Differential diagnosis of respiratory diseases part 2. Practice Nurse, 40(2), 33–41.
Retrieved from the Walden Library databases.

The authors of this article specify how to identify the major causes of acute breathlessness. Additionally, they explain how to interpret a variety of findings from respiratory investigations.

· SkillStat Learning, Inc. (2014). The 6 second ECG. Retrieved from http://www.skillstat.com/tools/ecg-simulator#/-home

This interactive website allows you to explore common cardiac rhythms. It also offers the Six Second ECG game so you can practice identifying rhythms.

· University of Virginia. (n.d.). Introduction to radiology: An online interactive tutorial. Retrieved fromhttp://www.med-ed.virginia.edu/courses/rad/index.html

This website provides an introduction to radiology and imaging. For this week, focus on cardiac radiography and chest radiology.

Media

· Laureate Education. (Producer). (2012). Advanced health assessment and diagnostic reasoning. Baltimore, MD: Author.

Note: You will use the case studies presented in the media, Advanced Health Assessment and Diagnostic Reasoning, to complete this week’s Discussion.

· Online media for Seidel’s Guide to Physical Examination

In addition to this week’s media, it is highly recommended that you access and view the resources included with the course text, Seidel’s Guide to Physical Examination. Focus on the videos and animations in Chapters 13, 14, and 15 that relate to the assessment of the heart, lungs, and peripheral vascular system. Refer to Week 4 for access instructions on https://evolve.elsevier.com/.

Optional Resources

· LeBlond, R. F., Brown, D. D., & DeGowin, R. L. (2009). DeGowin’s diagnostic examination (9th ed.). New York, NY: McGraw Hill Medical.

o Chapter 8, “The Chest: Chest Wall, Pulmonary, and Cardiovascular Systems; The Breasts” (Section 1, “Chest Wall, Pulmonary, and Cardiovascular Systems,” pp. 302–433)

Note: Section 2 of this chapter will be addressed in Week 10.

This section of Chapter 8 describes the anatomy of the chest wall, pulmonary, and cardiovascular systems. Section 1 also explains how to properly conduct examinations of these areas.

Assessing The Heart, Lungs, And Peripheral Vascular System

 
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pH of Common Materials

pH of Common Materials. How to Proceed

Read through the introductory materials below.
Open the Unit 1 Experiment Answer Sheet and complete the following Experiment exercises this unit:
Experiment 1 Exercise 1 – The Scientific Method (~30-45 min)
Experiment 1 Exercise 2A – pH of Common Materials (~30-45 min)
Experiment 1 Exercise 2B – pH and Buffers (~45-60 min)
Save your completed Unit 1 Experiment Answer Sheet and submit it no later than Sunday midnight CT.
The Scientific Method – Introduction

The Scientific Method is the basis for almost all scientific research. If you click on the Unit 1 Overview page, you can read about how the Scientific Method is conducted. You can also read about the process in your book on pp 14-17. One area of confusion often involves the difference between a hypothesis and a prediction. This is because many people use these terms interchangeably, but in fact, they are different. Here is how your book discerns the two:

Hypothesis – an answer to a question or explanation of an observation (p 14).

Prediction – an expected outcome if our hypothesis is correct; often worded as “if…then” (p15).

The purpose of this first exercise is to have you use the Scientific Method yourself. We will use the following web site. Be sure that you can access it and use it:

Glencoe/McGraw Hill. No date. The Scientific Method
http://www.glencoe.com/sites/common_assets/science/virtual_labs/ES01/ES01.html (Links to an external site.)

When you are ready to begin, use the instructions in the Unit 1 Experiment Answer Sheet and work through the exercise.

pH of Common Materials – Introduction

This unit we are also learning about some of the chemistry that is important in biological systems, such as pH. Be sure you have read pp 32-33 in your book and our online lecture this unit before beginning this exercise. The pH scale ranges from 0 to 14; a pH less than 7 is considered acidic and a pH greater than 7 is basic. The pH scale is logarithmic, which means that a solution with a pH of 3 is ten times more acidic than a solution with a pH of 4 and a hundred times more acidic than a solution with a pH of 5.

Acids and bases are not necessarily a bad thing. Many of the materials that we handle and eat and drink everyday vary in pH. Some of these materials are safe to handle, such as “weak” acids (e.g., soda, coffee). Stronger acids (e.g., battery acid) and bases (e.g., ammonia) can be quite caustic and damaging. One way to measure the pH of liquids is to use pH indicator paper; paper that turns a particular color depending on the pH of the solution. Anyone with a swimming pool or hot tub is probably familiar with such paper.

We will use a virtual lab to examine the pH of common solutions that you might have around the house. You will use the following website; be sure you are able to access and use it:

Glencoe/McGraw Hill. No date. pH of Common Solutions
http://www.glencoe.com/sites/common_assets/science/virtual_labs/E22/E22.html (Links to an external site.)

When you are ready to begin, open the Unit 1 Experiment Answer Sheet and follow the instructions to complete this exercise.

Buffers – Introduction

As you saw in the previous exercise, the pHs of common solutions vary across the pH scale! Yet our body is constrained to work within a very narrow pH range. Small changes in pH can alter the function of biologically important molecules such as enzymes, by breaking hydrogen bonds and denaturing these proteins. For this reason, in most organisms (such as ourselves), pH is very closely regulated. pH can be kept relatively constant by the use of buffers, chemicals which can absorb or release hydrogen ions to maintain a relatively steady pH.

In most vertebrate animals, blood pH must be maintained between 7.35 and 7.45. There are several biological buffers that work to maintain this pH; one of the more important being the carbonic acid – bicarbonate system:

H2O + CO2 <–> H2CO3 <–> H+ + HCO3-

In the reactions above, the double headed arrows indicate that each step is reversible. If carbon dioxide (CO2) levels increase in our blood, it can combine with water to form carbonic acid (H2CO3), which can break down to form bicarbonate (HCO3-) and hydrogen ions. This would shift the pH towards the acidic end. If the acidity levels become too high, the whole process will reverse, such that hydrogen ions are removed and carbon dioxide is produced; thereby shifting the pH towards the alkaline end. This is only one example of a biological buffer; there are several other systems involved, but they all operate in a similar manner.

The purpose of this exercise is to help you understand the chemistry of buffers. Be sure that you have read through the material on pp 32-33 in your book and this unit’s online lecture on The Chemistry of Life. For this exercise, you will use the following website (be sure your speakers are on):

McGraw-Hill Education. No date. Buffers
http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/buffer12.swf (Links to an external site.)

You may need to download and install a plugin to use this simulation, so test this simulation early in the unit in case you run into problems. When you are ready, open the Unit 1 Experiment Answer Sheet and follow the instructions there to complete this exercise.

WEEK 1 EXPERIMENT ANSWER SHEET Please submit to the Week 1 Experiment dropbox no later than Sunday midnight.

SUMMARY OF ACTIVITIES FOR WEEK 1 EXPERIMENT ASSIGNMENT

· Experiment 1 Exercise 1 – The Scientific Method

· Experiment 1 Exercise 2A – pH of Common Solutions

· Experiment 1 Exercise 2B — pH and Buffers

Experiment 1 Exercise 1: The Scientific Method

Be sure that you have read over the introductions to this week’s Experiments activities before starting. When ready, open the following website:

Glencoe/McGraw Hill. No date. The Scientific Method http://www.glencoe.com/sites/common_assets/science/virtual_labs/ES01/ES01.html

Scenario

You have been tasked to design the most efficient compost pile possible; one that can take organic waste material and quickly break it down into a form that can be applied as mulch. A compost pile typically involves:

· Green materials (e.g., fresh grass clippings, fresh leaves)

· Brown materials (e.g., dried grass, twigs, hay, dried leaves)

· Water

· Aeration

The efficiency of a compost pile is measured by how quickly organic matter is decomposed and this efficiency is dictated by the proper combination of the components listed above. Unfortunately, you do not know where to begin! Fortunately, you have a compost simulator that will allow you test a variety of compost designs before you have to construct your actual compost pile.

The purpose of this exercise is to use the Scientific Method to determine the best design for the most efficient compost pile. Note that the parameters that can be varied (using the slider bar) in our simulator are:

· Brown to Green Balance: 100% Green material, 100% Brown material or a combination of both

· Water Concentration: 0 to 100% water

· Number of turns per Month: 0 to 8 turns per month (the greater the number of turns the greater the aeration)

Hypothesis

We will start with the hypothesis that “an efficient compost pile needs lots of green material, a lot of water and a lot of aeration to be efficient”.

Question

1. Based on the on the hypothesis above and knowing the design parameters, write a reasonable prediction if the hypothesis is correct. Be sure to word it as an “If…then” statement (2 pts).

Procedure

A. Conduct an experiment (Experiment 1) to test the hypothesis above using the simulation program.

a. Set the design criteria using the sliders for Brown to Green Balance, Water Concentration and Number of Turns per month. Be sure to use settings based on the hypothesis; this is what you are testing.

b. Record your design criteria in Table 1 below for Experiment 1.

c. Click on the Calendar (Sept 1) in the simulation to start the experiment. When complete, record the Efficiency Meter reading.

Table 1. Design criteria and experiment results (2 pts)

  Brown to Green Balance Water Concentration Number of Turns per Month Efficiency

(High, Medium, Low)

Experiment 1        
Experiment 2        
Experiment 3

(Optional)

       

Questions

2. Was your prediction correct? If not, why do you think so (2 pts)?

3. Write an alternative hypothesis regarding an alternative compost pile design (2 pts).

4. Conduct another Experiment (Experiment 2) to test your new hypothesis using new design criteria (Click Reset to start over). Enter the necessary information in Table 1 above. What was the result of Experiment 2 (2 pts)?

Optional

If your second design was still not very efficient, conduct another Experiment and record your design criteria and results in the Table above.

Experiment 1 Exercise 2A: pH of Common Solutions

Be sure that you have completed your text book readings, have read through the online lecture and have read the introductory material for the Week 1 Experiment before starting. First, answer the following questions:

Questions

1. What is the definition of an acid? Your definition should include more than just a pH range. Provide one example of an acid. Cite your sources. (2 pts).

2. What is the definition of a base? Your definition should include more than just a pH range. Provide one example of a base. Cite your sources. (2 pts).

Open the pH simulation below to begin:

Glencoe/McGraw Hill. No date. pH of Common Solutions http://www.glencoe.com/sites/common_assets/science/virtual_labs/E22/E22.html

Procedure

A. Record the six substances shown across the top of the screen in Table 2 below (e.g., antacid, shampoo, battery acid, soft drinks…).

B. Enter a predicted pH value for each solution and a brief explanation for your choice.

Table 2. Predicted and measured pH values and your explanations (6 pts).

 

Substance Predicted pH Explanation for Prediction Measured pH
1        
2        
3        
4        
5        
6        
Optional additional solutions
7        
8        
9        
10        
11        
12        

C. Next, use the pH paper to measure the pH of each of the six solutions.

a. Click on the lose end of pH paper and drag into the first test tube.

b. It should change color. Drag the piece of paper over to the dispenser and use the color chart to estimate the pH. Record the measured pH in the Table above.

c. Use the up and down arrows beneath the name of the substance and set the value to the one you determined using the pH paper.

d. Repeat this procedure for the remaining five substances.

D. When you have recorded your pH values and set the counter to indicate the measured pHs, click on Check to see how you did. If necessary, retest any solutions you got wrong.

E. This simulation has twelve different solutions. Feel free to test them all if you would like. This is not required though! Click on Reset if you are interested.

F. When you are done testing the pHs, answer the questions below.

Questions

3. Which of your substances tested are considered an acid (1 pts)?

4. Which of your substances tested are considered a base (1 pts)?

5. What surprised you most about your results in this activity (1 pts)?

Experiment 1 Exercise 2B: Buffers

Before beginning, answer the following question:

Question

1. What is a buffer and briefly, how do they work? Cite your source (2 pts)?

Procedure

Open the buffer simulation below to begin (if necessary, copy the web address and past it into your browser). Be sure your speakers are turned on.

McGraw-Hill Education. No date. Buffers http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/buffer12.swf

A. Listen to the Introduction. If you need to listen to it again, reload the page.

B. Next, click on the Add Strong Acid, H+ button. Pay attention to the bars in the graph. They correspond to the level of the components in the beaker. You will need to watch them carefully.

Questions

2. Why does the green bar in the graph drop? Why does the purple bar in the graph rise? Explain what is occurring chemically (4 pts).

3. In the simulation shown, what happens to the pH in the beaker when HCl is added? How do you know this based on what you see in the graph (2 pts)?

4. What will happen to the pH if HCl is added after all of the acetate is used up? (1 pts)?

Procedure (continued)

C. Next, click on the Add Strong Base. OH-.

Question

5. What is formed when sodium hydroxide is added and how does this affect the pH (4 pts)?

 

Week 1 Experiment Grading Rubric

Component Expectation Points
Experiment 1 Exercise 1 Demonstrates an understanding of the Scientific Method and an ability to apply it (Table 1, Questions 1-3) 10 pts
Experiment 1 Exercise 2A Demonstrates an understanding of pH and how it applies to your everyday life (Table 2, Questions 1-5). 13 pts
Experiment 1 Exercise 2B Demonstrates an understanding of pH and the effect of buffers (Questions 1-5) 13 pts
TOTAL  

36 pts

Updated October 2013

pH of Common Materials

 
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