How Sweet It Is! - New Mission High Schoolnewmissionhigh.org/ourpages/auto/2014/1/27/53875088/How Sweet It Is_-2.pdf · They may find that their hydrometer touches the bottom and

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Chemistry

MATERIALS AND RESOURCES

EACH GROUP TEACHER

apronsbalancegogglespaper towelsstirring rod, glassballast, variety2 pipettes, thin stemspoon, plastic3 beverages, varietycalculator, graphing7 cups, 9-oz clear plasticgraduated cylinder, 100 mLmarker, Sharpie®

paper clip, smallruler, clear metricstrawsugartape, clearwater, distilled

aquarium, 10 gal.6 sodas, cans

How Sweet It Is!Constructing Consumer Claims

ABOUT THIS LESSON

This is a guided inquiry lesson that reinforces the relationship between concentration and density of solutions by constructing and

calibrating a hydrometer. Students will then conduct a comparative study of different store-bought beverages to make a claim regarding which products should be sold in schools. Students will use evidence both from research and their results from measuring the percent mass/mass of sugar for their tested beverages.

OBJECTIVES

Students will:• Engineer a hydrometer that will be used to gauge

solution concentration• Design an investigation to quantify the behavior

of the hydrometer depending on percent mass/mass of sugar in solution

• Create a calibration curve (i.e., standard curve) that can be used to determine the percent sugar in at least two beverages

• Make a claim for which types of beverages students should have access to on campus based on experimental evidence

LEVEL

Chemistry

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Chemistry – How Sweet It Is!

NEXT GENERATION SCIENCE STANDARDS

ASKING QUESTIONSDEFINING PROBLEMS

PLANNING/CARRYING OUTINVESTIGATIONS

ANALYZING ANDINTERPRETING DATA

PATTERNS SCALE, PROPORTION,AND QUANTITY

PS1: MATTER

ACKNOWLEDGEMENTS

Sharpie® is a registered trademark of Sanford L.P., A Newell Rubbermaid Company.

REFERENCES

This activity was adapted from the “Beverage Density Lab” experiment in Introduction to Chemistry, Volume 1 in the FlinnChemTopic™ Labs series, Cesa, I. (ed.), Batavia, IL: Flinn Scientific, 2002.

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COMMON CORE STATE STANDARDS

(LITERACY) RST.9-10.1

Cite specific textual evidence to support analysis of science and technical texts, attending to the precise details of explanations or descriptions.


Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks, attending to special cases or exceptions defined in the text.


Translate quantitative or technical information expressed in words in a text into visual form (e.g., a table or chart) and translate information expressed visually or mathematically (e.g., in an equation) into words.

(MATH) HSN-Q.A.1

Use units as a way to understand problems and to guide the solution of multi-step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs and data displays.

(MATH) HSN-Q.A.3

Choose a level of accuracy appropriate to limitations on measurement when reporting quantities.

(MATH) HSS-ID.B.6C

Represent data on two quantitative variables on a scatter plot, and describe how the variables are related. Fit a linear function for a scatter plot that suggests a linear association.

(MATH) HSS-ID.C.7

Interpret the slope (rate of change) and the intercept (constant term) of a linear model in the context of the data.

(MATH) HSS-ID.C.8

Compute (using technology) and interpret the correlation coefficient of a linear fit.

CONNECTIONS TO AP*

2CHEMISTRYCHEMISTRYAPAP

A.3 Solutions are homogenous mixtures in which the physical properties are dependent on the concentration of the solute and the strengths of the interactions among the particles of the solutes and solvents.

*Advanced Placement and AP are registered trademarks of the College Entrance Examination Board. The College Board was not involved in the production of this product.

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TEACHING SUGGESTIONS

Overview of the Lesson

Begin with a discrepant event. Encourage students through your questions to develop the concepts of density and sugar content.

Provide time and resources for students to research the controversy about the health effects of food items with high sugar content and their prevalence in schools.

Assist students in the construction of a hydrometer and the development of a standard curve to establish a relationship between two quantifiable variables.

Allow students to conduct their comparative study using the hydrometer they have calibrated, monitoring student progress and giving feedback.

Begin the lesson with a demonstration of floating sodas. Have a desktop aquarium or other large clear container filled with tap water. Gently place a variety of unopened canned sodas into the water. Typically, the diet sodas float and the other sodas sink. Occasionally, a soda will remain suspended midway in the water.

Be sure to try this demo before the students arrive in the classroom. Remove any sodas that do not “behave.” Regular soda that is very old or has been exposed to high temperatures tends to go flat and may float. You can prepare the system ahead of time or lower the cans carefully while students watch, giving them the opportunity to predict each can’s behavior.

In leading the discussion, ask students to think about what they see and try to come up with an explanation. Some suggested questions are:

• What do we know about why things float or sink?• Is the density less than water or greater than

water, and how can you tell? • Is there any pattern to which drinks float and

which drinks sink? • What is the difference in the composition of the

drinks that sink versus those that float? • If sugar and sugar substitutes have similar molar

masses, why don’t all cans behave the same? Do you think the concentration of each sweetener is the same?

It is important to emphasize that although diet sodas do not contain sugar, they do contain a sweetening substance that has mass and contributes to the density of the solution. Many students will want to say that one has sugar and the other has “nothing.”

We can think more critically to determine that there must be much fewer molecules of sweetener (less concentration) in the diet soda than sugar molecules in regular soda. This is why it takes one small package of artificial sweetener to sweeten iced tea to the same level as many spoonfuls of sugar.

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TEACHING SUGGESTIONS (CONTINUED)

From this point, the segue to the next section of the lesson revolves around the questions:

• Exactly how much sugar is in regular soda?• How many students drink sodas? What kinds?

How often? What volumes?• Other than water, what non-soda drinks do

students consume? How often? What volumes?

At this point, students can have access to the introduction of the lesson. You can do this by providing each student with a handout or projecting the introduction to the class on the board. After the class has read it, they will need time to look up some sources online and summarize their findings in the Pre-Lab Exercises. Alternatively, you can compile a list of resources that present both sides of the argument for the health effects of sugary beverages on children.

Students could even complete the Pre-Lab Exercises as part of a homework task if the demonstration is done in the class period leading up to the investigation. Student research can lead to discussion of topics like diabetes, obesity, juice versus soda, artificial sweeteners, caloric intake, and exercise.

Students will also need clarification on how to make a percent mass/mass solution if they have never made one previously:

1. Place a plastic cup on an electronic scale and record the mass and tare the scale.

2. Add a mass of solute to the cup and record this value.

3. Without resetting or taring the scale, pour solvent into the cup. Record the final mass of the solution.

4. The percent mass/mass will be the mass from Step 2 divided by the mass from Step 3, then multiplied by 100.

In other words, if a student wanted to make a 5% m/m solution, they would add 5.00 g of solute to the cup and then enough water to make the total mass 100.0 g.

Students are now ready to begin Part I of the investigation. They are provided with instructions for manipulating a straw into a hydrometer, a device meant for measuring the specific gravity or density of a solution. Hydrometers are most commonly used to test the alcohol level during the fermentation process in beer. As the sugar is converted to alcohol, the density of the solution goes down. When the density stabilizes, all of the sugar has been consumed and the beer is done fermenting.

Table A. Some Resources

www.ameribev.org/news-media/news-releases-statements/more/311/

www.ameribev.org/nutrition-science/school-beverage-guidelines/

www.cdc.gov/healthyyouth/nutrition/facts.htm

www.hsph.harvard.edu/nutritionsource/sugary-drinks-fact-sheet/

http://pediatrics.aappublications.org/content/113/1/152.full

www.cbsnews.com/8301-204_162-57593133/artificial-sweeteners-could-lead-to-obesity-diabetes

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Commercial hydrometers are available and online videos are easily accessible for how to read them. In this exercise, students will be constructing their own hydrometers but the selection of proper ballast will depend on the straws you have provided. Drinking straws are easy to obtain from fast-food establishments and coffee shops. Some straws are made with a greater density plastic and a larger diameter. Thinner drinking straws will respond to density changes with greater sensitivity and require less ballast.

The ballast can be marbles, one-hole rubber stoppers, dice, or other small dense objects. You should experiment to determine the option that works best with your straws. You can choose to provide an assortment of straw and ballast options and allow students to engineer their hydrometer according to the information provided, or you can specify the type of straw and ballast each group should use. Though more efficient, the latter option removes inquiry and engineering elements from the activity.

Students will need to actively test their hydrometer using a 100-mL graduated cylinder and distilled water. They may find that their hydrometer touches the bottom and they need to add less ballast, or else the hydrometer floats too much and they need to add more ballast. You should also inspect the design to see how easy it will be to dry the equipment between readings. The hydrometer should not be a significant source of cross-contamination.

In Part II, students are given a guiding question. This question sets up the context for the investigation and students will need to to structure their experimental design with appropriate consideration to number of samples, range of concentrations, and designation of variables for graphical analysis. You will need to engage student groups in a discussion on these aspects as you monitor progress.

If student groups struggle with experimental design, or are proposing insufficient data collection, direct them to answer Question 1 and Question 2 in Part II of the Analysis section. Those two questions can also spark the conversation with the group that will allow you to gauge their understanding.

For example you might approach a group with, “I am interested in learning about your approach to this experiment. Can you tell me about the variables you have? How many solutions are you going to test, and what are their concentrations?” All students should identify the independent variable as percent mass/mass and the dependent variable as the hydrometer reading. They should arrive at a need for three to five samples with a maximum concentration of near 30%, which is a natural parameter set by the volumes of sample students must make and the maximum mass of sugar they are given to use.

Students can decide to prepare samples individually or propose some sort of serial dilution. If they opt for a serial dilution, they should be able to tell you that they must dilute based on mass rather than volume. For example, if you take 50 g of a 10% m/m solution and add enough water to reach 100 g, the new concentration is now 5% m/m.

Once students have data, they will be able to perform a linear regression. This is a recurring skill in many labs but some students will need assistance to complete the graphing task. It is your discretion whether you will allow students to hand-graph their data or not. Discuss the usefulness of a calibration curve in chemistry. By using a series of known (concentration, hydrometer reading) ordered pairs, we can create a mathematical line that will allow us to interpolate the concentration of any sugar solution we can measure with the hydrometer.

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Because the hydrometer number correlates with the length exposed above the solution level, students should see that the hydrometer reading increases with increasing concentration. This is due to the increasing density of the sugar solutions with increasing concentration, causing the hydrometer to be more buoyant in solution.

In Part III, the comparative studies that students can conduct will be limited by the beverages that are available for them to test. Options include flat sugar sodas, flat diet sodas, sports drinks, uncarbonated or flat energy drinks, juice (“100% juice” and juice “from concentrate”), fruit punch, sweet tea, and so on. For example, students may decide to test sodas versus juices, or juice versus non-soda options. The main idea is for students to see how virtually all of these contain appreciable amounts of sugar.

Sodas get much of the blame for sugar intake but often “100% juice” contains just as much, if not more, sugar. It is branded as being a healthier option, though students may come to a different conclusion based on the reading from their hydrometers. It is an

opportunity to apply their engineered hydrometer to answer a question they have.

Relating it back to issues on school campuses is intended to increase engagement and let students make a claim that they feel is relevant to them. For example, students may claim that because juice is just as sugary as soda, all drink options should be sold in school vending machines. Conversely, they might argue that because juice is so sugary, neither juice nor soda should be sold. Given the flexibility inherent in the claim, students will need to support it with adequate evidence and reasoning.

The structure of their response to Question 3 in Part III of the Analysis should model the C-E-R framework for scientific explanations. In the process of developing their claim, students will also have to reflect on their own habits as consumers, which may show up as part of their evidence and reasoning. However, their personal opinions should not be present in their response. For example, it is inadequate to claim that, “Sodas should be sold on school campuses because they taste delicious.”

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Chemistry – How Sweet It Is!Chemistry – How Sweet It Is!

PRE-LAB EXERCISES

1. Summarize your findings from the questions and prompts presented in the introduction.Answers will vary. In general, students will find that there is a movement to ban sodas in schools because of their sugar and caffeine content. Flavored waters, sports drinks, juices, and milk are not as targeted as sodas. Health issues like diabetes and obesity often lead the argument for why sugary sodas should be not be sold on campuses.

2. Using online resources, obtain the nutrition facts for both an apple and 100% apple juice. Compare and contrast the two products with a Venn diagram. Table A is an example of what a student might find online. Sample links are also provided.

Table A. Nutritional Facts

Apple Both Apple Juice

4 g fiber/182 g serving

0 g fat 0 g fiber/248 g serving

Vitamin A 0 g protein 4% of daily Vitamin C

14% of daily Vitamin C

No cholesterol

2% of daily calcium and iron

Sugar is the greatest mass on nutrition data

www.fns.usda.gov/fdd/facts/hhpfacts/New_HHPFacts/Fruits/HHFS_APPLES_FRESH_F510-515_Final.pdf

http://nutritiondata.self.com/facts/fruits-and-fruit-juices/1822/2

4. Describe how you would prepare 100. g of a 10.0% m/m sugar solution.Place a plastic cup or beaker on a scale and “tare” the scale. Add 10.0 g of sugar to the beaker. Without taring the scale again, add enough water to make the total mass of the solution 100. g, not counting the mass of the beaker.

DATA AND OBSERVATIONS

PART I: CONSTRUCT THE HYDROMETER

In the space provided, draw a diagram of your hydrometer. Be sure to identify your ballast and report the hydrometer reading in distilled water.

Answers will vary depending on the ballast and straws used.

PART II: CALIBRATE THE HYDROMETER

Record and organize your data in the space provided for the trials you conducted.

Example data is shown in Table B.

Table B. Hydrometer Calibration

% Mass/Mass Sugar Hydrometer Reading

0 5.3

6.07 7.2

11.5 8.5

19.3 9.7

27.6 11.5

34 12.8

PART III: USE THE HYDROMETER

Record and organize your data in the space provided for the products you tested.

Answers will vary depending on the products tested.

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ANALYSIS


1. Would a straw with a larger diameter require more or less ballast? Justify your answer.A straw with a larger diameter would require more ballast. The hydrometer will float at the point where the weight of water displaced is equal to the weight of the portion submerged. Because a wider straw displaces more water, a greater amount of ballast is required to make sure the hydrometer is able to float with the end close to the bottom of the graduated cylinder.

2. If poured slowly enough, you can float a layer of ethanol in water. Predict how the hydrometer would behave in a sample of pure ethanol compared to pure water, and explain your reasoning. Ethanol is less dense than water. The hydrometer will float at the point where the weight of the ethanol displaced is equal to the weight of the portion submerged. Using the same hydrometer, a greater volume of ethanol must be displaced to achieve that balance. This means that the ethanol will be more submerged in ethanol than in water, and the hydrometer reading will be less. In other words, the hydrometer is more buoyant in liquids with greater density.

Figure A. Hydrometer reading vs. percent mass/mass sugar

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ANALYSIS (CONTINUED)


1. Identify the independent (x-axis) and dependent (y-axis) variables in your experiment.The x-axis has the independent variable of “% m/m” and the y-axis displays the dependent variable of “hydrometer reading.”

2. What were your considerations in determining the number of data points to collect? How did you decide on the minimum and maximum concentrations to test?Answers will vary but all students should agree that at least three data points are needed. Students may suggest that they limited their data to 3–5 points in the interest of time and materials. Minimum and maximum concentrations depend on how many data points students decide to collect and how they manage the 100 g of sugar they are allotted.

3. Using graphing software, plot your results for Part II and determine a regression equation that fits your data. See Figure A.a. Report the equation here along with the

correlation coefficient, and attach a copy of your graph. y = 0.2118x + 5.690

b. What is the significance of the y-intercept and how does it compare to your own data?The y-intercept of 5.69 represents the hydrometer reading in pure water. Experimentally, that value was 5.3.

4. Identify the physical property of the solution that is responsible for the trend in hydrometer readings as concentration increases.Increasing the percent mass/mass of sugar increases the density of the solution. The change in density is responsible for the trend in hydrometer readings.


1. Using your hydrometer readings, determine the percent sugar for the beverage samples tested in your study and rank the products in order of increasing concentration.Answers will vary depending on the beverages tested. They typically range from 8–20%.

2. Obtain the nutrition facts from your teacher for the beverages tested. a. Calculate the carbohydrate concentrations in g/

mL of solution.Answers will vary depending on the beverages tested. Most serving sizes for beverages are given in units of volume on the nutrition labels.

b. Does the data from the nutrition facts confirm your experimental results? Why or why not?Answers will vary. Ideally, the experimental data will support the rankings for sugar content. The units of concentration are not the same but the ranking should be.

3. Compose a position about what products should be accessible to students as on-campus consumers. Justify your position using evidence from your research and your investigation.Answers will vary depending on the study that students conducted. Students may claim that because even sports drinks and juices contain large amounts of sugar, all beverages should be sold on campuses. Alternatively, their findings may lead them to claim that none of the tested beverages should be sold to students.

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CONCLUSION QUESTIONS

1. To convert concentrations from percent mass/mass to molarity, you must be able to do the following two conversions:• Convert grams of solute to moles of solute• Convert grams of solution to a volume of

solution in litersFor each conversion, identify the conversion factor(s) you would need to perform the calculation. No actual calculations are necessary.• Molar mass of the solute is required for the

first conversion.• Density of the solution is required for the

second conversion.2. All the soft drinks tested were allowed to go

“flat.” If freshly opened soda were used in this experiment, would the calculated concentration be greater than, less than, or the same as a “flat” sample? Justify your answer.The density would be less due to the carbon dioxide gas in the bubbles as gases are mostly empty space. If the density of the beverage were less, the hydrometer would give a lower reading. This would correlate to a lesser concentration

than the “flat” soda would have. Students may argue that the bubbles will cling to the hydrometer and give it increased buoyancy. This would cause the hydrometer reading to be too high and result in an inaccurately larger concentration. Both defenses use evidence to support a reasonable claim and are good responses.

3. The primary source of energy for carbon-based life is the Sun. Explain how sugars are the ultimate connection between the Sun and all living things in the carbon cycle. You may support your explanation with drawings and diagrams.Living things in the carbon cycle get their energy from glucose, a sugar made by plants in the process of photosynthesis. Plants use the sugar they produce to live. Animals must eat plants or other animals that eat plants (or other animals that eat other animals that eat plants, and so on). No matter what, all living things require carbohydrates, the most important of which is made in plants using energy from the Sun.

1Copyright © 2013 National Math + Science Initiative, Dallas, Texas. All rights reserved. Visit us online at www.nms.org.

Chemistry – How Sweet It Is!Chemistry

MATERIALS

aprons

balance

goggles

paper towels

stirring rod, glass

ballast, variety

2 pipettes, thin stem

spoon, plastic

3 beverages, variety

calculator, graphing

7 cups, 9-oz clear plastic

graduated cylinder, 100 mL

marker, Sharpie®

paper clip, small

ruler, clear metric

straw

sugar

tape, clear

water, distilled

How Sweet It Is!Constructing Consumer Claims

Most have heard the saying, “An apple a day keeps the doctor away.” Can the same be said for apple juice? Certain beverages have a really bad name with regard to health, particularly the health of children,

and that name is surprisingly not “calories” but “carbohydrates.” Some schools, districts, and even cities are taking a stand against the accessibility of many sweet treats on campuses.

As a Pre-Lab Exercise for this investigation, arm yourself with a little background information. Which drinks are getting cut in schools (perhaps yours), which get to stay, and why? Consider what the American Beverage Association has to say and whether it lines up with other health organizations such as the Centers for Disease Control and Prevention (CDC).

In this investigation, you will conduct a comparative study to experimentally determine the “carb” concentration of store-bought beverages. Using your data, you will develop a position about what products should be accessible to students as on-campus consumers.

To take quantitative measurements, you will create a tool called a hydrometer using a straw and some simple materials. Before you can conduct your study, you will first need to make the hydrometer and determine how its behavior in liquids provides you with useful information.

PURPOSE

The purpose of this experiment is to experimentally determine the percentage of sugar in a variety of beverages using a calibrated hydrometer.



PROCEDURE


1. Obtain a straw, ruler, and marker. Starting from one end, mark the straw at 0.5 cm increments along three quarters of the straw’s length.

2. Fold down approximately 1 cm of straw at the end that is not marked. Slide a small paper clip over the fold until half the length of the clip is on the straw. To secure the clip in place and ensure the straw’s end stays folded, wrap a piece of transparent tape tightly around the bottom of the straw. The end of the straw that is now sealed will be referred to as the “bottom” of the straw. The open end of the straw represents the “0” mark.

3. Mark every five lines moving down the straw such that you can read the numbers when the straw is vertical with the open end facing up.

4. Using materials provided by your teacher, attach an appropriate amount of ballast to the bottom of your straw. Your ballast should be compact enough to fit inside a 100-mL graduated cylinder and heavy enough to make the hydrometer float upright in the cylinder when filled to the 100-mL mark. In distilled water, the bottom of the hydrometer with ballast should be approximately 1 in. from the bottom of the cylinder but not more than 2 in.

5. To ensure that the hydrometer is floating freely, give the straw a spin. Take a reading of the distilled water with the hydrometer to the nearest tenth of an interval. Record your value on your student answer pages.

ballast

Figure 1. Student hydrometer



PROCEDURE (CONTINUED)


What relationship exists between the hydrometer readings and the percent mass/mass (%m/m) of sugar in solution? Design an experiment that will allow you to answer this question.

In your investigation, you may use up to 100 g of sugar. Make notes about your procedure in the space provided, record your findings on your student answer pages, and perform relevant calculations for the Analysis.


Consider the assortment of juices, sodas, and beverages provided by your teacher. The nutrition labels have been removed but you have been provided with all names and brands.

Design and conduct a comparative study using your hydrometer that will allow you to develop a position about what products should be accessible to students.



PRE-LAB EXERCISES

1. Summarize your findings from the questions and prompts presented in the introduction.

2. Using online resources, obtain the nutrition facts for both an apple and 100% apple juice. Compare and contrast the two products with a Venn diagram.

3. Describe how you would prepare 100. g of a 10.0% m/m sugar solution.



DATA AND OBSERVATIONS


In the space provided, draw a diagram of your hydrometer. Be sure to identify your ballast and report the hydrometer reading in distilled water.



DATA AND OBSERVATIONS (CONTINUED)


Record and organize your data in the space provided for the trials you conducted.


Record and organize your data in the space provided for the products you tested.



ANALYSIS


1. Would a straw with a larger diameter require more or less ballast? Justify your answer.

2. If poured slowly enough, you can float a layer of ethanol in water. Predict how the hydrometer would behave in a sample of pure ethanol compared to pure water, and explain your reasoning.





1. Identify the independent (x-axis) and dependent (y-axis) variables in your experiment.

2. What were your considerations in determining the number of data points to collect? How did you decide on the minimum and maximum concentrations to test?

3. Using graphing software, plot your results for Part II and determine a regression equation that fits your data. a. Report the equation here along with the correlation coefficient, and attach

a copy of your graph.

b. What is the significance of the y-intercept and how does it compare to your own data?

4. Identify the physical property of the solution that is responsible for the trend in hydrometer readings as concentration increases.





1. Using your hydrometer readings, determine the percent sugar for the beverage samples tested in your study and rank the products in order of increasing concentration.

2. Obtain the nutrition facts from your teacher for the beverages tested. a. Calculate the carbohydrate concentrations in g/mL of solution.

b. Does the data from the nutrition facts confirm your experimental results? Why or why not?

3. Compose a position about what products should be accessible to students as on-campus consumers. Justify your position using evidence from your research and your investigation.



CONCLUSION QUESTIONS

1. To convert concentrations from percent mass/mass to molarity, you must be able to do the following two conversions:• Convert grams of solute to moles of solute• Convert grams of solution to a volume of solution in liters

For each conversion, identify the conversion factor(s) you would need to perform the calculation. No actual calculations are necessary.

2. All the soft drinks tested were allowed to go “flat.” If freshly opened soda were used in this experiment, would the calculated concentration be greater than, less than, or the same as a “flat” sample? Justify your answer.

3. The primary source of energy for carbon-based life is the Sun. Explain how sugars are the ultimate connection between the Sun and all living things in the carbon cycle. You may support your explanation with drawings and diagrams.



GOING FURTHER

OPTION 1

There is no recommended daily allowance (RDA) for sugar. However, the official U.S. guidelines say that a 2000 calorie per day diet should consume a maximum of 40 g of sugar.

Keep a log and write down the grams of sugar in each item that you consume over the next 24 hours, and see how you compare to the U.S. guidelines for sugar consumption. Be explicit with assumptions you make in approximating the sugar content of food that does not have a label.

OPTION 2

Calibrate your hydrometer for potassium nitrate and measure the percent mass/mass for a saturated solution at room temperature. Additionally, convert to grams of potassium nitrate per 100 grams of water and compare this with the accepted value for solubility at the temperature you investigated.

Documents

How Sweet It Is! - New Mission High Schoolnewmissionhigh.org/ourpages/auto/2014/1/27/53875088/How Sweet It Is_-2.pdf · They may find that their hydrometer touches the bottom and