Sodium Analysis in
Potato Chips
ILF Background Information
Chemistry 111
March 2011
Gwen, Nathalie and Monica
Sodium in Potato Chips
• Frito-Lay Lay's Potato Chips - Original (for a small bag,
28.3 g) claims to have 180 mg of sodium.
• Old Dutch Potato Chips - Original (for small bag, 28 g)
claims to have 130 mg of sodium.
• Humpty Dumpty Potato Chips - Original (for a small bag,
16 g) claims to have 100 mg of sodium.
After looking at these sodium counts, we are going to do
an analysis to see if these companies are true to their
nutrition facts, or if they are a little off...or even way off.
What is the chemical formula, chemical structure, molar
mass and the CAS Registry number of the analyte you
will be working with?
The analyte we are working with is Sodium Chloride, its chemical formula
being 2Na + Cl2. The structure of this chemical is based as a typical ionic
structure, meaning it is a compound, where we cannot state just how many
ions there really are. There could be billions of sodium and chloride particles
all constantly moving about each other. This chemical also contains ionic
bonding, with the sodium having one electron on its outer layer and chlorine
needing one more electron for its outer layer. They work together by giving
and receiving the electrons needed to fill their ring and forming an ion. The
formation of sodium chloride is arranged in such a way that each particle is
surrounded by oppositely charged neighbors, such as the picture below.
The Molar Mass of the chemical is 58.44277 g/mol and has a CAS Registry
Number of 7647-14-5.
Find and print out a free MSDS for
the chemical you are studying.
http://www.jtbaker.com/msds/englishhtml/s
3338.htm
What are the health benefits of consuming the
chemical you are working with?
When thinking of Sodium Chloride, most people’s first reaction is that it is
bad and unhealthy for you. This is true to the consumption of large
quantities; however this chemical also contains many health benefits.
Sodium is needed by your body to help with proper blood flow, it helps
maintain the electrolyte balance in and out of your cells and is needs to be
used to replenish these electrolytes, especially after exercising. Having a
good salt to water ratio within your body provides good metabolism, and the
chemical can also show early signs of health problems by examining it in
the blood flow. Overall, your body needs certain amounts of sodium each
day to properly function and carry out your basic needs.
What are the health risks of consuming too much of the
chemical you are working with?
It is widely known that the quantity of salt we tend to ingest nowadays is not
beneficial to our health at all. The amount the general population does
intake on a daily basis has risen so high over the years because of the ever
growing processed and "convenient" food industries. Most anything we buy
in stores are loaded with salt as preservatives of merely to add flavour. This
huge difference has proven to cause many health problems in the human
population such as hypertension, also known as high blood pressure,
which elevates the systemic arterial blood pressure in particular.
Hypertension in itself may lead to strokes, eyesight trouble, heart failure
and causes a lower life expectancy. Other health risks of ingesting high
amounts of sodium are osteoporosis and stomach cancer. A certain
amount of salt and sodium are in fact necessary to our bodies to maintain
balance, but in the same way too much can throw off the equilibrium of
fluid in our bodies and cause you to retain water. Overall, people in the
world are eating much too much salt and it causes many health risks that
nobody wants.
What is the normal or acceptable amount of your
group's analyte, in the substance you will be analyzing?
The average sodium intake amongst adults in the UK is 3.7 grams
per day (equivalent to 9.5 grams or around 2 tsp of salt) and is well
above the amount needed to maintain normal functions in a
temperate climate. The RNI (recommended nutrient intake) for
sodium is only 1.6 grams per day.
Investigate the instrumentation or techniques required to carry
out the analysis you will do.
The Instruments needed for this analysis of Sodium Chloride are:
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Sodium Ion Selective Electrode
Sodium Ion Selective Electrode fill solution
Pipette for fill solution
PASCO CI-6738 ISE (Ion Selective Electrode) Amplifier
Science Workshop 2.2.5 of greater
PASCO Science Workshop Computer Interface
Semi logarithmic 4-cycle graph paper for preparing calibration curves
Magnetic stir plate
Lab-ware made of plastic for all low level instruments (do not use glass)
Equipment/Instruments need for solutions are:
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Deionized or distilled water for solution and preparation
Ionic Strength Adjuster (ISA) 4 M NH4Cl/4 M NH4 OH
Sodium Electrolyte Storage Solution 5 M NaCl
How does the instrumentation or technique work to
measure the substance you are looking for?
After crushing the potato chips and making a solution with it and the distilled
water, you put the ISE (without the cap) into the solution.
The instrumentation measures the substance by measuring the conductivity
of the water - the solution has a charge because of the ions we are working
with. By measuring the conductivity of the solution, we can analyze the
concentration of sodium, seeing if the chips contain more than 1.6 g of
sodium, the recommended nutrient intake per day. Before using the ISE,
you need to make up a fill solution that contains sodium ions. This allows
the ISE to recognize what ion we are looking for in the solution, and will
then pick out the sodium in the solution of potato chips and distilled water.
What other chemicals are required to do
the analysis?
The chemicals needed are distilled water,
Sodium Electrode Storgage Solution,
Ammonium Solution, Ammonium Hydroxyde,
Ionic Strength Adjuster and Sodium Chloride.
Look up and print out the MSDS for each
chemical required to do the analysis.
Distilled Water MSDS
Sodium Electrode Storage Solution MSDS
Ammonium Chloride MSDS
Ammonium Hydroxide MSDS
Ionic Strength Adjuster MSDS
Sodium chloride MSDS
Outline the steps required to carry out the analysis.
Electrode Preparation Remove rubber cap from electrode
Hook up the electrode to amplifier and computer
Experiment Preparations 1. Buy different brands of potato chips
2. Take the chips and crush them up as much as possible, to as little as possible a size (use
a mortar)
3. Weigh out a measurement of the chips, 10 grams being a good starting point
4. Whatever the weight you chose, add 10 times as much water to the chips to form a
solution
5. Place the solution in the Magnetic Stirring Plate overnight so that the sodium will be
extracted from the chips
6. After the solution is mixed in the beaker it must be transferred to a larger Volume Flask
for more precise measuring
7. Stir the solution again with the Magnetic Stirring Plate to be sure you have a
homogenous solution
8. Measure 50 ml of the solution into a beaker and add 1 ml of ISA
9. Place the ISE into the sodium solution so that it can measure the amount of sodium
found
10. Be sure to record all data in your Lab Book
Make a list of the skills you will need to
have training in, in order to perform the
analysis properly.
- Before performing this analysis, you should be sure to
have the proper WHMIS training as well as basic
computer skills.
- For the experiment itself, you should know how to use the
Magnetic Stirring Plate as well as the ISE (refer to
manual for instructions).
References
Question One
Kurtus, Ron. (2004, January). Chemistry equations. Retrieved from http://www.school-forchampions.com/chemistry/equations.htm
Clark, Jim. (2010, February). Ionic stuctures. Retrieved from
http://www.chemguide.co.uk/atoms/structures/ionicstruct.html
Encyclopedia, Britannica. (2008, February). Sodium chloride stucture. Retrieved from
http://www.britannica.com/EBchecked/topic/552185/sodium-chloride-structure
Baker, JT. (2009, August 17). Sodium chloride. Retrieved from http://www.jtbaker.com/msds/englishhtml/s3338.htm
Question Two
Baker, JT. (2009, August 17). Sodium chloride. Retrieved from http://www.jtbaker.com/msds/englishhtml/s3338.htm
Question Three
Hannemen, R. (2001). Diet&lifestyle salt research. Internet Health Library.
http://www.internethealthlibrary.com/DietandLifestyle/salt-health-danger-research.htm
MediLexicon, . (2004). Salt (sodium chloride), what it is and how it affects your health. Medical News Today.
http://www.medicalnewstoday.com/articles/13273.php
Question Four
MediLexicon, . (2004). Salt (sodium chloride), what it is and how it affects your health. Medical News Today.
http://www.medicalnewstoday.com/articles/13273.php
References Cont.
Question Five
MediLexicon, . (2004). Salt (sodium chloride), what it is and how it affects your health. Medical News Today.
http://www.medicalnewstoday.com/articles/13273.php
Question Six
PBoyle, Peter . (1997). Sodium Ion Selective Electrode. (1997). Instruction Manuel and Experiment Guide . PASCO
scientific.
Pictures found at:
http://pipettetip.cn/html/Product/view_21.html
http://www.pasco.com/featured-products/ion-selective-electrodes/page_3.cfm
Question Seven
PBoyle, Peter . (1997). Sodium Ion Selective Electrode. (1997). Instruction Manuel and Experiment Guide . PASCO
scientific.
Question Eight
PBoyle, Peter . (1997). Sodium Ion Selective Electrode. (1997). Instruction Manuel and Experiment Guide . PASCO
scientific.
References Cont.
Question Nine
Decagon, (2007). Material safety data sheet distilled water 40464. Pullman, Washington: Decagon Devices.
Science Lab.com. Material safety data sheet sodium nitrate, 5m ionic strength adjustor msds. Houston, Texas: Science
Lab Chemicals & Laboratory Equipment.
Thermo, . Orion 841101 sodium electrode storage solution material safety data sheet. Beverly, MA: Thermo Scientific.
Baker, J.T. (2007). Ammonium chloride msds. Phillipsburg, NJ: Malinckrodt Chemicals.
Science Lab.com, . Material safety data sheet ammonium hydroxide msds. Houston, Texas: Science Lab Chemistry
and Laboratory Equipment.
Question Ten
PBoyle, Peter . (1997). Sodium Ion Selective Electrode. (1997). Instruction Manuel and Experiment Guide . PASCO
scientific.
Question Eleven
PBoyle, Peter . (1997). Sodium Ion Selective Electrode. (1997). Instruction Manuel and Experiment Guide . PASCO
scientific.