DOCSLIB.ORG

Shaking for Suds: Which Type of Water Is the Hardest?

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Shaking for Suds: Which Type of Water Is the Hardest? Shaking for Suds: Which Type of Water is the Hardest? Difficulty Time Required Short (2-5 days) Prerequisites None Material Availability Readily available Cost Very Low (under $20) Be sure to wear safety goggles if you are using Safety glass jars for testing. Abstract Do you want your hair to be shiny after you wash it? Do you want your clothes to stay bright and soft after laundering, and last a long time? You might think that a special shampoo or detergent can make this happen, but in this chemistry science fair project, you'll discover that how well people and things get clean has a lot more to do with the type of water used for washing than any special shampoo or soap. Did you know that water can be classified as either soft or hard? Soft water lathers and cleans better than hard water. Using this clue, you'll test different common water types to figure out which type is the softest and which is the hardest. Objective To determine the relative hardness of different common water types. Credits Kristin Strong, Science Buddies Introduction Do you love to take a bubble bath filled with thick, hissing suds that you can sink down into? Do you like to take those bubbles and coat yourself from head to toe with white foam until you look like old man winter? Or do you sculpt the bubbles into towers and mountains, or hide your bath toys in them, so that your toys can't get eaten by an evil shark? Figure 1. This photo shows rubber duckies enjoying a bubbly bath. (Wikimedia, 2006.) However you enjoy your bath bubbles, you might be surprised to learn that when you pour a small amount of liquid bubble soap into the water coming out of your faucet, the amount of bubbles you can make depends upon the hardness of your water. You might be thinking "What? Water isn't hard! You can easily put your hand down into it, right?" That's true, but the term hardness, when used to talk about water has a different kind of meaning. Hardness is a word that geologistsand other water scientists, like hydrologists, use to describe how many tiny particles of minerals are in the water. Minerals are the building blocks of rocks. Minerals are not made by people, but by nature. If you've ever seen a diamond, emerald, or a ruby, you've seen a special and expensive kind of mineral, called a gem. In water, the common minerals that you will find are calcium and magnesium cations (pronounced CAT-eye-un). Cations are atoms that are missing some of their electrons (the negatively charged parts of an atom). Figure 2. This photo shows examples of beautiful minerals. (Mila Zinkova, 2007). How do these minerals get into water? To understand this, you first need to know a little bit about acids and bases. Pure water is neutral, which means it is not acidic or basic; however, rainwater is slightly acidic, like orange juice. As this slightly acidic rainwater passes through mineral deposits, like the calcium-containing limestone that was used to build the Great Pyramids of Egypt, it reacts with the minerals and changes them into a form that can be dissolved in water, just as you can dissolve a spoonful of sugar in a glass of water. In this way, calcium and magnesium cations get into the water supply. Is the hardness of water the same everywhere? No, take a look at the map below of the United States from the United States Geological Survey. The areas in deep blue are where the water is the "softest," with low levels of dissolved minerals in the water. The areas in medium blue and white have greater levels of dissolved minerals, and the levels in red are areas where the water is the hardest, with high levels of calcium and magnesium cations in the water. So, if you live in states like Maine, Vermont, the Carolinas, Alabama, or Georgia, you might have never even heard of hard water, but if you live in states like Utah, Wyoming, Colorado, Nebraska, or west Texas, hard water is something you deal with every day. Figure 3. This map of the United States shows by color where water levels are hardest and softest. The red areas have the most dissolved calcium cations in the water and the hardest water, while the dark blue areas have the least dissolved calcium cations in the water, and therefore the softest water. (USGS, 2005.) What happens when you have hard water? Well, the harder the water (the more calcium and magnesium hardness minerals you have in the water), the more soap or detergent you need to get things clean. In other words, harder water makes less soapy lather. So, if you live in an area with hard water and you want to wash your clothes, dishes, or yourself, it will be harder to get these things clean than if you live in an area with soft water—water without a lot of dissolved minerals. Hard water interferes or reduces lathering (the formation of suds or bubbles). Because of hard water, a film can build up on shower doors and walls, or bath tubs, sinks, and faucets. Hair washed with hard water might look less shiny than hair washed with soft water. Clothing fabrics might be dull, gray, and scratchy, and wear out more quickly. Finally, water pipes in your house, and appliances that use water might not work very well over time because of build-up of hard water deposits. Is it bad to have hard water? No. In fact, the minerals in hard water are thought to contribute to human health. Hard water is mainly just a bother when it comes to cleaning, or in keeping pipes and water-using appliances working well. So, how do you measure the hardness of water? There are chemistry kits that will tell you approximately how many tiny parts of calcium and magnesium you have in your water, but in this chemistry science fair project, you are going to use liquid soap to compare the hardness of different kinds of water. You will see how high of a bubbly lather you can create with each type of water. Questions What is the difference between hard and soft water? Is the hardness of water the same everywhere? Materials and Equipment Permanent marker Shaking jars, cups, or bottles with lids (3) Should be equally sized and equally shaped Any size is a possible option, but containers that are similar in size to typical water bottles work well. Can be glass or clear plastic, though plastic does not have the risk of breakage. If you use glass jars, then you will also need safety goggles. Safety goggles are available from an online supplier such as Carolina Biological catalog #646706C. Distilled water (1 gallon) Bottled mineral water (1 gallon), sometimes called "spring water"; not the carbonated kind Tap water (1 gallon) Metric measuring cup Eye dropper; available at drug stores Liquid dishwashing soap (1 bottle) The kind for washing dishes by hand; not the kind for dishwashers A stopwatch that has a seconds reading A helper Lab notebook Disclaimer: Science Buddies occasionally provides information (such as part numbers, supplier names, and supplier weblinks) to assist our users in locating specialty items for individual projects. The information is provided solely as a convenience to our users. We do our best to make sure that part numbers and descriptions are accurate when first listed. However, since part numbers do change as items are obsoleted or improved, please send us an email if you run across any parts that are no longer available. We also do our best to make sure that any listed supplier provides prompt, courteous service. Science Buddies does participate in affiliate programs with Amazon.comsciencebuddies, Carolina Biological, and AquaPhoenix Education. Proceeds from the affiliate programs help support Science Buddies, a 501( c ) 3 public charity. If you have any comments (positive or negative) related to purchases you've made for science fair projects from recommendations on our site, please let us know. Write to us at [email protected]. Experimental Procedure Preparing to Test 1. Label the jars with the permanent marker. a. You can write down 1, 2, or 3, or write the name of each water type on a different jar, so that you can keep track of which type of water is inside each jar. b. The three types of water you will be testing are distilled water, bottled mineral water, and tap water. 2. Decide how much water you want to put in each jar. a. Filling the jar 1/5 full with water works well. For example, this would mean putting 100 milliliters (mL) of water into a 500 mL water bottle. b. In your lab notebook, write down the amount of water you will add to each jar. (You will be adding the same amount of water to each jar.) 3. Using the metric measuring cup, measure out and add the amount of water you decided on (in step 2) to each appropriate jar. a. For example, you may put 100 mL of distilled water in jar 1, 100 mL of bottled mineral water in jar 2, and 100 mL of tap water in jar 3. b. Get down so that you are eye-level with the mark as you are measuring the water in the measuring cup. 4. While each jar is on a level surface, draw a straight line to mark the height of the water.
Load more

Recommended publications
  • Sodium Dodecyl Sulfate-Coated Alumina and C18 Cartridge for The
    J. Braz. Chem. Soc., Vol. 19, No. 8, 1523-1530, 2008. Printed in Brazil - ©2008 Sociedade Brasileira de Química 0103 - 5053 $6.00+0.00 Article Sodium Dodecyl Sulfate-Coated Alumina and C18 Cartridge for the Separation and Preconcentration of Cationic Surfactants Prior to their Quantitation by Spectrophotometric Method Mohammad Ali Karimi,*,a,b Reza Behjatmanesh-Ardakani,b Ali Aghaei Goudi b and Sara Zali b aDepartment of Chemistry, Faculty of Science, Payame Noor University (PNU), Sirjan, Iran bDepartment of Chemistry, Faculty of Science, Payame Noor University (PNU), Ardakan, Iran Um novo método de extração em fase sólida foi desenvolvido para separar e pré-concentrar traços de tensoativos catiônicos, tais como, brometo de dodeciltrimetilamônio (DTAB), brometo de cetiltrimetilamônio (CTAB) e cloreto de cetilpiridínio (CPC). Esse método é baseado na sorção do tensoativo aniônico (AS−), dodecilssulfato de sódio (SDS), sobre a superfície de γ-alumina, + enquanto um cartucho C18 é utilizado para a pré-concentração dos tensoativos catiônicos (CS ). O método espectrofotométrico, utilizado para a determinação dos tensoativos catiônicos, baseia-se na competição entre o corante catiônico, azul de metileno (MB+), e o CS+, para associação e formação do complexo SDS. O íon complexo formado (MB+) pode ser quantitativamente substituído pelo CS+, levando a um aumento da absorvância medida em 662 nm. Foram estabelecidas ótimas condições experimentais para a separação, pré-concentração e determinação dos tensoativos catiônicos. Sob essas condições otimizadas, realizou-se a pré-concentração (2×) e os resultados mostraram que a determinação do CPC, DTAB e CTAB poderia ser realizada nas faixas de concentração de 1×10-5-2×10-4, 4×10-5-5×10-4 and 5×10-5-5×10-4 mol L-1, respectivamente.
    [Show full text]
  • ELGA Veolia Water Guide V6.Pdf
    A GUIDE FOR LABORATORIES Pure labwater guide An essential overview of lab water purification applications, monitoring and standards. Dedicated to Discovery 2 Dedicated to Discovery PURE LABWATER GUIDE Inside 3-5 Introduction 6-16 Research and analysis applications 17-20 Clinical diagnostics 21-23 Healthcare 23-47 Water purification overview 48 Glossary 51 Further reading 3 Dedicated to Discovery PURE LABWATER GUIDE The pure labwater guide Introduction The Pure LabWater Guide is an essential resource for individuals who use pure water or wish to learn more about the subject. Providing an overview of water purification requirements, techniques and applications in science and medicine, this educational guide will enable you to choose the correct grade of water and most reliable method of production at an economical cost to both your budget and the environment. CHALLENGES: vary significantly in purity both from There are 5 classes of impurities found IMPURITIES AND one geographical region to another in natural and drinking water: and from season to season. VARIATIONS IN • Suspended particles In today’s laboratories, the availability DRINKING WATER • Dissolved inorganic compounds of pure water is essential, and Water for most laboratory and clinical while domestic consumers consider • Dissolved organic compounds applications is usually purified from tap water to be “pure”, laboratory • Microorganisms & biomolecules drinking water. However, the unique scientists and healthcare professionals ability of water to dissolve (to some regard it as
    [Show full text]
  • Drinking Water Treatment: Distillation Bruce I
    ® ® University of Nebraska–Lincoln Extension, Institute of Agriculture and Natural Resources Know how. Know now. G1493 (Revised December 2013) Drinking Water Treatment: Distillation Bruce I. Dvorak, Extension Environmental Engineering Specialist Sharon O. Skipton, Extension Water Quality Educator water as it is boiled in the distiller. Such compounds will not Homeowners are increasingly concerned about be completely removed unless another process is used prior contaminants in their water supply that may affect to condensation. See the section in this NebGuide on treat- health or cause taste, odor, or nuisance problems. Dis- ment principles for further discussion of ways distillers may tillation, one of the oldest methods of water treatment, remove VOCs. is an effective method for reducing many impurities The boiling process during distillation generally inacti- found in water. This NebGuide discusses the process vates microorganisms. However, if the distiller is idle for an and related equipment used for household drinking extended period, bacteria can be reintroduced from the outlet water treatment by distillation. spigot and may recontaminate the water. Water Testing Contaminants Removed from Water by Distillation Regardless of which water treatment system is con- Distillation can remove nearly all impurities from sidered, the water first should be tested to determine what water. Compounds removed include sodium, hardness substances are present. Public water systems routinely test compounds such as calcium and magnesium, other dis- for contaminants. Water utilities are required to publish solved solids (including iron and manganese), fluoride, Consumer Confidence Reports (CCRs), which inform con- and nitrate. Operated properly, it effectively inactivates sumers on the source of the water, contaminants present, microorganisms such as bacteria, viruses, and protozoan potential health effects of those contaminants, and methods cysts (though protozoan cysts are not likely to be found in of treatment used by the utility.
    [Show full text]
  • An Applied Review of Water Desalination Technologies and an Introduction to Capillary-Driven Desalination
    water Article Looking Beyond Energy Efficiency: An Applied Review of Water Desalination Technologies and an Introduction to Capillary-Driven Desalination Seyedsaeid Ahmadvand 1,* , Behrooz Abbasi 1,*, Babak Azarfar 1, Mohammed Elhashimi 2, Xiang Zhang 2 and Bahman Abbasi 2,* 1 Department of Mining and Metallurgical Engineering, University of Nevada, Reno, NV 89557, USA; [email protected] 2 School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Bend, OR 97702, USA; [email protected] (M.E.); [email protected] (X.Z.) * Correspondence: [email protected] (S.A.); [email protected] (B.A.); [email protected] (B.A.) Received: 4 March 2019; Accepted: 1 April 2019; Published: 4 April 2019 Abstract: Most notable emerging water desalination technologies and related publications, as examined by the authors, investigate opportunities to increase energy efficiency of the process. In this paper, the authors reason that improving energy efficiency is only one route to produce more cost-effective potable water with fewer emissions. In fact, the grade of energy that is used to desalinate water plays an equally important role in its economic viability and overall emission reduction. This paper provides a critical review of desalination strategies with emphasis on means of using low-grade energy rather than solely focusing on reaching the thermodynamic energy limit. Herein, it is argued that large-scale commercial desalination technologies have by-and-large reached their engineering potential. They are now mostly limited by the fundamental process design rather than process optimization, which has very limited room for improvement without foundational change to the process itself. The conventional approach toward more energy efficient water desalination is to shift from thermal technologies to reverse osmosis (RO).
    [Show full text]
  • Health Effects of Long Term Consumption of Water Low in Calcium, Magnesium Or TDS: Studies from Eastern Europe
    (paper presented at the International Symposium on Health Aspects of Calcium and Magnesium in Drinking Water, Baltimore, Maryland, USA, 24-26 April 2006) Health effects of long term consumption of water low in calcium, magnesium or TDS: studies from Eastern Europe Frantisek Kozisek Address: Frantisek Kozisek, M.D., Ph.D,; National Institute of Public Health, Srobarova 48, CZ- 10042 Prague, Czech Republic. Tel.: + 420 267 082 302. Fax: + 420 267 082 271. E-mail: [email protected]. Introduction The relationship between the consumption of soft or low mineralized water and the incidence of some diseases has been discussed in literature since the 1960’s. Some of the recent reviews agree that regular consumption of such water poses a health risk. Nevertheless, critics found some weak points, e.g. the English language bias, as most reviews only included publications in English. This contribution intends to show that in Central and Eastern Europe, multiple authors paid attention to this issue and a lot of studies that have significantly supplemented existing knowledge have been available in several national languages. One of the reasons why desalinisation has, from the very beginning, been considered not only a technical but also public health problem could well be the national methods of managing water supplies. Such surveillance was conducted in the former USSR and other European communist satellites by the Public Health Service; in other words, by medically educated personnel. In the former USSR, the first cue to possible health risks from low mineralized water was provided in the mid 20th century by negative empirical experience gained with the consumption of water from melted snow during polar and climbing expeditions and of distilled water prepared on transoceanic ships.
    [Show full text]
  • The Role of Fluid Intake in the Prevention of Kidney Stone Disease
    Ahead of Print Turk J Urol • DOI: 10.5152/tud.2020.20155 ENDOUROLOGY Systematic Review The role of fluid intake in the prevention of kidney stone disease: A systematic review over the last two decades Kithmini Nadeeshani Gamage1 , Enakshee Jamnadass1 , Sadaf Karim Sulaiman2 , Amelia Pietropaolo2 , Omar Aboumarzouk3 , Bhaskar K. Somani4 Cite this article as: Gamage KN, Jamnadass E, Sulaiman SK, Aboumarzouk O, Pietropaolo A, Somani BK. The role of fluid intake in the pre- vention of kidney stone disease: A systematic review over the last two decades. Turk J Urol 5 June 2020. DOI: 10.5152/tud.2020.20155. [Epub Ahead of Print] ABSTRACT Objective: The incidence of kidney stone disease (KSD) is rising worldwide; hence, more focus must be directed toward its etiology and risk factors. Increasing fluid intake is recommended as the most ideal prevention; yet, there is inconsistent evidence surrounding optimum volumes and types of fluid that affect stone formation. This review aimed to analyze the published literature on fluid intake and types of fluid consumed and their impact on KSD prevention. Material and methods: Papers were acquired from databases: MEDLINE, EMBASE, PubMed, CINAHL, and Cochrane Library. Included English language studies that involved adults consuming beverages along with a standardized diet in relation to KSD. Those failing to control dietary factors were excluded. ORCID IDs of the authors: K.N.G. 0000-0002-2993-5876; Results: After an initial search of 1099 papers, 9 (541 participants) were included in the final review. Six E.J. 0000-0001-7998-8063; varieties of water and ten different types of juices were investigated.
    [Show full text]
  • Galvanic Corrosion Prevention Guide for Water Cooling Systems
    WATER COOLED DEVICES Galvanic Corrosion Prevention Guide for Water Cooling Systems November 2017 | White Paper Water Created by Cooled Helen E. Kane, Advanced Energy Industries, Inc. Devices Abstract Table of Contents This report details best practices for reducing the risk of galvanic corrosion in water cooling system designs. Galvanic Summary and Background 2 corrosion will manifest if the following conditions exist: Research Findings 2 Best Practices Recommendations 5 1 Electrically dissimilar metals in contact (or both in References 7 contact with the same water) 2 Electrolyte present (could be as simple as condensation) Time is another critical factor. The mean time to failure can be short or long, depending on the combination of conditions 1 and 2. This report provides the galvanic series for general metals and compatibility. In addition, it lists preventative measures to avoid issues in open loop cooling water systems. 2 GALVANIC CORROSION PREVENTION GUIDE FOR WATER COOLING SYSTEMS Summary and Background This report details best practices for reducing the risk of galvanic corrosion in mechani- cal and electro-mechanical cooling system designs. Galvanic corrosion, sometimes called bimetallic or dissimilar metal corrosion, is when one metal in a system experiences corrosion due to an electro-chemical reaction with a different metal and an electrolyte in the same system. Galvanic corrosion has been experienced in designs with dissimilar metals used in Advanced Energy products that use water cooling. Because conditions that promote gal- vanic reactions can exist inside Advanced Energy units due to the environment and running conditions, some simple best practices will help reduce the risk of galvanic corrosion failure.
    [Show full text]
  • WHITE PAPER Effects of Impurities on Lead-Acid Batteries
    WHITE PAPER Effects of Impurities on Lead-Acid Batteries Introduction Effects on the Battery In lead-acid batteries, water purity can have a major effect on The mineral content may be minimal in some water. The gassing product performance. Water usage needs to be viewed as a priority effects from charging a storage battery, coupled with evaporation, for maximum performance. The popular misconception is that any may leave behind mineral contaminates in the electrolyte solution. As type of water can be used. Natural waters may vary considerably a result, the minerals will have a cumulative effect inside the battery. in the amount of impurities they contain. Some factors include the Table 1 shows the effects of the different impurities. source of the water and the time of year. Throughout the country there are various water sources with different amounts of impurities. Table 1 Contaminates in the water source play a large part in the performance Recommended Maximum Allowable Impurities in Water for Battery Use and life of a battery. Types of Water Impurity Parts Per Million Effects of Impurity The most common type of water used in batteries is distilled water. Color Clear and “White” - Other types are deionized water and water from reverse osmosis. Ordinary tap water should not be used because it may contain an Suspended Matter Trace - excessive amount of impurities that will degrade battery performance. (See Table 1 for acceptable maximum allowable impurities in water Total Solids 100.0 - for battery use). Organic and 50.0 Corrosion of positive plate Volatile Matter Distilled water is produced by distillation, a process in which water is boiled, the steam is collected and then condensed back into water.
    [Show full text]
  • Practical Approach to Fluid Therapy
    Practical Approach to Fluid Therapy (Q) n 0 "'O '-< Frank A. Mongini, D. V.M. ......'"i Cotati, California (JQg > 8 I'm sure all of you recognize the necessity of This solution can be made in any quantity and (D ......'"i intravenous fluids as a therapeutic means in the can be autoclaved. When analysed at a laboratory, (") treatment of many disease conditions. The major its composition is as follows: § factors preventing us from utilizing fluids as Table 2 >00 00 frequently as we'd like, is usually either the cost of Composition of Homemade Lactated Ringer's Solution 0 the fluids, or the time and effort spent in (")...... administration. With these problems in mind, we Na 144 mEq/L a...... have attempted and I feel succeeded in arriving at a K 4.0 mEq/L 0 Cl 111 mEq/L ~ 0 fluid that is balanced and a means of adminis­ H-i tration that is efficient. to A comparison price-wise points out the value 0 In searching for the ideal type of fluid, the < economically of the homemade solution. 5· following objectives should be met: a) properly (D Table 3 balanced, b) effective, c) efficiency in preparation, ~ ~ and d) economical. l L 3.0 Gallons (") There are numerous commerical preparations ,-+-...... Eltrad L.A. $0.30 $4.35 ,-+-...... available. In Table 1, I have listed some of the 0 Homemade Lactated $0.13 $1.58 ~ (D common fluids and their relative values. Ringer's Solution '"i 00 Tabk l 0 Our next concern is the administration of these "'O Common Elcctrolytcs-Valucs E:xprcsscd in mEq/L (D fluids.
    [Show full text]
  • Water Health Series Bottled Water Basics
    Table of Contents Bottled water basics ....................................... pg.2 Advice for people with severely compromised immune systems (Sidebar) ............................. pg2 Know what you’re buying .............................. pg.3 Taste considerations ........................................ pg.4 Bottled water terms (Sidebar) ..................... pg.4 Begin by reading the label ............................. pg.5 Type of water and source ............................... pg.5 Contaminants and methods of treatment .... pg.6 Common bottled water treatments (Sidebar) ........................................ pg.6 Certification ........................................................ pg.7 Contact information ......................................... pg.8 FDA bottled water standards (Sidebar) .......................................... pg.8 Advice for people with sonal use, end-of-tap, under sink) severely compromised Bottled water basics filters that remove particles one water provided by public water suppliers; FDA sets immune systems micrometer or less in diameter. standards for bottled water based on EPA standards. Bottled water is the fastest growing drink choice Filters that use reverse osmosis, Bottled water and tap water are both safe to drink if Some people may wish to take those labeled as “absolute one in the United States, and Americans spend bil- they meet these standards, although people with special precautions with the water micron filters,” or those labeled as lions of dollars each year to buy it (Beverage severely
    [Show full text]
  • United States Patent Office Patented Dec
    3,356,570 United States Patent Office Patented Dec. 5, 1967 2 (2) Name: Molar sodium lactate 3,356,570 Formulation: COMPOSTION FOR TREATING SHOCK Harvey R. Butcher, Jr., St. Louis, Mo., assignor to The 85% lactic acid----------------- --------- cc. 400 Trustees of Barnes Hospital, St. Louis, Mo., a trustee Sodium hydroxide pellets----------------- gm. - 195 ship of Missouri Phenol red indicator--------------------- mg-- 4 No Drawing. Fied Nov. 27, 1964, Ser. No. 414,420 Freshly distilled water q.S. ----------------cc. 4000 5 Claims. (C. 167-58) pH range 6.8-8.4. The present invention relates to a composition for Procedure: treating shock in animals, including human beings, as 0 Measure 400 cc. 85% lactic acid into wide mouth well as lower animals, and in its specific and preferred Pyrex flask. Add 1000 cc. distilled water and phenol red embodiment it consists of a lactated Ringer's solution indicator (4 mg.). Weigh NaOH pellets, placing con having a pH of about 7.4 to 9.1, which pH is obtained tainer in cold water to prevent container from over-heat normally by the addition of sodium hydroxide. The op ing. Mix with above solution. Bring volume to 4000 cc. timum pH is about 8.2. 5 with distilled water. Boil for 30 minutes. Cool solution, Heretofore, shock has been treated by giving intraven q.s. again to 4000 cc. Filter. Pour into bottles which have ously some solution such as Ringer's solution or lactated Ringer's solution. Such solutions normally have a pH been previously washed and treated. on the acid side.
    [Show full text]
  • What's So Special About Bottled Drinking Water?
    What’s so special about bottled drinking water? Testing water for hardness Annotation This laboratory teaches students about water hardness, polar and non-polar molecules, and anions and cations. Primary Learning Outcome: After the lesson is completed students should be able to understand that polar and nonpolar ions do not usually mix without an emulsifier like soap. Students should be able to recognize a drawing of a polar and non-polar molecule. Students will also know that a cation is an ion with a positive charge and an anion is an ion with a negative charge. Georgia Performance Standards: SC7. Students will characterize the properties that describe solutions and the nature of acids and bases. Total Duration: 45 minutes Materials and Equipment: 1. 5 test tubes with rubber stoppers 2. 1 test tube holder 3. Ivory soap solution 4. Eye dropper or pipette 5. 5 types of water (distilled, spring, tap, purified, carbonated, mineral, SmartWater, etc.) 6. Graduated cylinder Procedures: Set up To prepare the soap solution you will need a bar of Ivory soap. Using a knife, scrape the bar to obtain about 7 grams of powdery shavings. This makes enough for over 50 groups to do the lab. Slowly stir these into 560 ml of distilled water. Prepare this 12-24 hours before it will be used for the lab. This should result in a thick, milky white liquid. Estimated Time: 15 minutes Lesson materials to be attached: Introduction Pre-lab questions Procedures Data table Post-lab questions Grading key Web Links: Drinking Water: Hard Water http://ianrpubs.unl.edu/water/g1274.htm Chemistry of Hard and Soft Water http://chemistry.about.com/cs/howthingswork/a/aa082403a.htm Laboratory Procedures 1.
    [Show full text]