Effects of Chemical Constituents of Laundry Detergents andMethods of Stain Removal

Sarah M. Don

Chemistry EEISemester 4, 2008Dr Stolarchuk

September 17, 2008

Contents

1 Background 31.1 Types of Stains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.1.1 Organic Stains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.1.2 Inorganic Stains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.1.3 Pigments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2 Stain Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2.1 Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2.2 Surfactants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.2.3 Phosphates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.2.4 Acids and Bases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.2.5 Enzymes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.2.6 Oxidising Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51.2.7 Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2 Aim 6

3 Procedure 6

4 Results 7

5 Product Evaluation 85.1 Sard Wonder Soap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.2 Baking Soda . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.3 OMO Liquid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.4 Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85.5 Napisan Oxy-Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95.6 Bleach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95.7 Lemon Juice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95.8 Tap Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95.9 Overall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

6 Conclusion 11

A Stain Removal Solutions’ Effectiveness on Different Stains 13A.1 Aim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13A.2 Equipment and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13A.3 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13A.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

B Determining the pH of the Stain Removal Solutions 15B.1 Aim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15B.2 Equipment and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15B.3 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15B.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

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C Conductivity of the Stain Removal Solutions 16C.1 Aim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16C.2 Equipment and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16C.3 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16C.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

D Solubility of the Stain Removal Solutions 17D.1 Aim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17D.2 Equipment and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17D.3 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17D.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

E Redox Indicator Test 18E.1 Aim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18E.2 Equipment and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18E.3 Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18E.4 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

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1 Background

There are many different methods for the removal of stains. However, various types of stain removers workdifferently on varying stains. It is important to understand the science behind why different stain removalsolutions work in order to know what kind of solvent to use on a certain kind of identifiable stain. A stain’sconstituents’ molecular structure and composition determine how well and in what way the stain can beremoved from the fabric.

1.1 Types of Stains

1.1.1 Organic Stains

An organic molecule is one that is made up of a carbon chain with oxygen, hydrogen and other non-metalsattached. Some of such compounds are polar while others are non-polar, depending on what functionalgroups are attached. Polymers, such as polysaccharides, are organic, and often need to be broken down intoshorter chains (even monomers) before they can be dissolved.

1.1.2 Inorganic Stains

Inorganic compounds can usually be dissolved by inorganic solvents when a replacement or addition reactionoccurs. The interaction between an inorganic, ionic solvent and solute can be altered by redox reactions. Ifthe molecules of a stain are involved in a redox reaction, the composition of the stain changes into anothercompound so that it may become colourless and appear as though it has been washed out.

1.1.3 Pigments

Most pigments contain chromophores which are molecules that contain double bonds that absorb and emit aparticular wavelength of light which defines the colour of the stain. Tannin, an organic compound, is a kindof pigment with a red-brown colour found in coffee and red wine. Tannin, however, is not very responsiveto oxidation and basic solvents, thus making it difficult to remove from fabrics. The green colour of grass isprovided by the pigment chlorophyll, also an organic chromophore.

1.2 Stain Removal

Different types of stain removal solutions interact differently with various types of stains. The polarity, sizeand solubility of the molecules in both the stain and the stain removal solution determine how well the staincan be lifted from the fabric. When considering what kind of solvent dissolves a particular substance, theidea that ‘like dissolves like’ can be adopted. Water (which is inorganic) dissolves inorganic compounds,while only organic solvents dissolve organic substances. To dissolve an organic compound in an inorganicsolvent (and vice versa), a surfactant must be added to the solvent (see Section 1.2.2).

1.2.1 Water

Water is considered a universal solvent. Because of the bent water molecule’s polarity, it is able to dissolveother polar molecules as well as ionic compounds. As mentioned in Section 1.2, water is an inorganic solvent,so it can only dissolve inorganic substances. However, with the aid of surfactants (such as detergent), organicsubstances can also be suspended in an aqueous solution.

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1.2.2 Surfactants

Surfactants are molecules that have one polar end and one non-polar end, making them able to reducethe surface tension of a solvent or reduce the interfacial tension between two solutions. Micelles, such asphospholipids, have a hydrophobic (non-polar) and a hydrophilic (polar) end that allow it to form a layerbetween water-based and oil-based substances (see Figure 1).

Figure 1: Left - Micelle in water with hydrophilic head on the outside.Right - Micelle in oil-based solution with hydrophobic end facing outward. (Wikipedia, 2008)

Surfactants can emulsify compounds that are not normally soluble in a particular medium. (Wikipedia,2008) The micelles form a coating on the insoluble particles, and because the micelle itself is soluble becauseof the head group’s favourable interactions with the water, the previously insoluble compound can then bedissolved. (Donker, 1998)

1.2.3 Phosphates

Phosphates are ionic compounds that contain a phosphate group (PO4−3). The part of blood that causes

the rust-coloured stain to occur is iron oxide (Fe2O3). Iron phosphate, however, is colourless, so solutionsthat contain phosphates are able to ‘remove’ blood stains because a displacement reaction occurs betweenthe iron oxide and the phosphate compound.

Fe2O3 + 2XPO4 → 2FePO4 + X2O3

The oxide group in Fe2O3 is replaced with a phosphate group to make FePO4, which is colourless. However,the actual mass of the biological material remains in the fabric unless surfactants are present to dissolve theorganic material as well.

1.2.4 Acids and Bases

The concept of ‘like dissolves like’ can also be applied to acids and bases. Most soaps contain sodiumhydroxide (NaOH) an alkali which is polar and therefore interacts favourably with water and can dissolvebasic. Lemon juice contains citric acid, which is a reducing agent as well as an acid-solvent, so stains thatare acid-based or oxidants can be easily suspended from the fabric. So if the approximate pH of a stain isknown, a cleaning solution of similar pH can be effectively used to remove the stain.

1.2.5 Enzymes

Some laundry detergents contain enzymes. Certain molecules of the stain latch onto the active site of anenzyme as the substrate to form an enzyme/substrate complex, and the enzyme breaks the molecule intosmaller sections that may be more easily dissolved (see Figure 2). Such enzymes suited to laundering usually

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work best in warm water, and so instructions on laundry detergents’ packaging to use warm water is sometimesan indication that the detergent contains enzymes.

Figure 2: Enzyme breaking up stain molecule into smaller pieces

On the other hand, sometimes laundry detergents incorrectly state on the packaging that they containenzymes. Often, however, what they really mean is that the laundry detergent contains oxidising agents.

1.2.6 Oxidising Agents

Bleach, a solution of sodium hyperchlorate (NaOCl) and hydrogen peroxide (H2O2), is a very strong oxidisingagent. When bleach oxidises a chromophore, some of the energy released in the redox reaction is taken fromthe double bonds, leaving the chromophore with only single bonds. Because these single bonds don’t allowfor the release of trapped energy in the form of photons at visible wavelengths, the pigment stain appearscolourless. If only some of the double bonds are broken, however, the stain may only appear faded or as anentirely different colour. (Wikipedia, 2008)

Oxidation reactions also release oxygen molecules. Because it is less dense than the liquid, the oxygengas rises to the top of the solution, disturbing the molecules of the stain. By disturbing the stain moleculeswith oxygen, the parts of the stain may become dislodged from the fabric. So oxidising agents can be helpfulin removing stains. (Wikipedia, 2008)

1.2.7 Temperature

Besides facilitating the function of enzymes, temperature has other effects on how well laundry detergents (orany other solvents) work. By increasing the temperature, the particles in both the stain and the solvent aregiven more energy, causing them to vibrate faster. This assists the solvent in dislocating the stain particlesfrom the fibers of the fabric, and also makes it more difficult for the stain to reattach. Too much heat cansometimes cause certain types of stain to become ‘fixed’ or ‘set’ into the fibers of the fabric which makes thestain particles even harder to remove. However, cold water may not allow the chemical ingredients in thestain removal solution to do their job properly.

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2 Aim

The objective of this investigation was to identify the effectiveness of certain laundry detergents and stainremoval methods by comparing their constituents’ chemical properties.

3 Procedure

1. Extensive background research was done on the constituents of stains and laundry detergents, as wellas other stain removal methods.

2. The experiments in steps 5-9 were designed.

3. MSDS sheets of the hazardous chemicals required to conduct the experiments were obtained. (SeeAppendix F)

4. A journal containing research, notes, ideas, planning and the results of the experiments was maintainedthroughout the investigation.

5. A cleaning test was conducted to identify which stains could be removed by which stain removalsolutions. (See Appendix A)

6. The pH of the stain removal solutions was identified. (See Appendix B)

7. The conductivity of the stain removal solutions was tested. (See Appendix C)

8. The solubility of the stain removal solutions in water, oil, acid and basic solvents. (See Appendix D)

9. The redox potential of the stain removal solutions was determined. (See Appendix E)

10. This research paper was written to explain the science behind the results of this extended experimentalinvestigation.

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4 Results

Table 1: Collaboration of the Results from all the Chemical TestsConducted on the Stain Removal Solutions

Cleaning Solution pH Conductivity Solubility Redox PotentialSard Wonder Soap 9 2 w*, o*, b XBaking Soda 8 5 w, a, b ×Omo Liquid 7 1 w, a, b XDrive 11 3 w, b XNapisan Oxy-action 10 4 w, a, b XBleach 8 4 w, a, b XLemon Juice 4 4 w, o*, a, b* XTap Water 7 1 w, a, b ×

Solubility: w = water, o = oil, a = acid, b = base*partially dissolved

Table 2: Effectiveness of Stain Removal SolutionsCoffee Beetroot Blood Grass Red Wine Foundation Ink None

Sard Wonder Soap 4 5 4 4 4 3 2 5Baking Soda 2 4 4 2 3 0 0 5OMO Liquid 4 4.5 4.5 4 4 1 2 5Drive 3 4.5 4 3 3 2 1 5Napisan Oxy-Action 4.5 5 4 4.5 4.5 1 0.5 5Bleach 5 5 5 5 5 0 0 4.5Lemon Juice 3 3 2 2 2 0 0 4.5Tap Water 3 3 3 1 3 0 0 5

Stain Removal Effectiveness: 0 = no change, 5 = no trace

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5 Product Evaluation

5.1 Sard Wonder Soap

Sard Wonder Soap is alkaline and contains surfactants, reducing agents and some ionic compounds. It is alsosoluble in basic solvent and partially soluble in water and oil. This suggests that the soap contains moleculeswith the properties of a base, fats (surfactants), polar and possibly ionic compounds. Most of the stainsresponded well1 to Sard Wonder Soap, except foundation and ink. However, foundation and ink respondedbetter to Sard Wonder Soap than to any other cleaning solution.

Most of the stains’ strength of colour was heavily reduced, however traces of the stains did remain. Themass of the stains was most likely removed by the surfactants and oxidising agents in the soap. Both organicand inorganic parts of the stain were able to be removed because of the polarity of the water in which theSard Wonder Soap was dissolved, and the glycerol that the soap most likely contained.

5.2 Baking Soda

Baking soda is a basic salt, which is why it was such a good conductor and ineffective on all the stains otherthan beetroot and blood. The results from the experiments conducted in this investigation were not conclusiveenough to determine how the beetroot stain was able to be mostly removed. However, the remaining yellow-brown traces of the beetroot stain were most likely due to some form of organic, non-polar pigment. The redcolour of the blood stain was removed, however a yellow-brown colour and stiffness of the fabric remained.As phosphates are able to replace the oxide group in iron oxide (see section 1.2.3), a possible explanationfor the absence of the iron oxide colour after the test is that the bicarbonate group in sodium bicarbonate(baking soda) replaced the oxide group in iron oxide, which has a yellow colour. (Wikipedia, 2008)

Fe2O3 + 6NaHCO3 → 2Fe(HCO3)3 + 3Na2O

The results that showed that baking soda does not have redox potential may explain why it was not aseffective as other cleaners in removing the other stains.

5.3 OMO Liquid

Although OMO Liquid was neutral and a poor conductor, it effectively cleaned five of the stains. Its effec-tiveness was most likely due to its redox potential and solubility in water, acid and base. Unlike most of theother stain removal solutions, OMO Liquid worked relatively well on the ink stain. OMO Liquid also workedwell on the same stains as bleach, which suggests that contains a form of bleach or other oxidising agent.

5.4 Drive

Drive laundry detergent worked similarly to baking soda in that it only worked well on the beetroot andblood stains. The packaging of the laundry power suggested the use of warm water, which implies the possiblepresence of enzymes. As only cold water was used, it is possible that Drive was not able to work to its fullpotential.

Drive did show some impact on the foundation stain. However, it was not soluble in oil, which suggeststhat the Drive was able to remove some other part of the foundation stain other than the oil - possibly partor one kind of pigment.

1received a rating of 4 or greater in Table 2

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5.5 Napisan Oxy-Action

With its basic nature, high conductivity, redox potential and solubility in water, acid and base, NapisanOxy-Action had an effect on all the stains. However, like most of the other stain removal solutions, NapisanOxy-Action was not so good at removing the foundation and ink stains. Napisan Oxy-Action’s conductivityindicates that it contains ionic particles, and its redox potential (and effectiveness on the same stains asbleach) suggests that it contains solid sodium hypochlorate (bleach).

5.6 Bleach

Bleach was clearly the most efficient stain removal method. It is likely that the other cleaning solutionsthat worked fairly well on the same kinds of stains contained a small amount of some kind of bleach. Asdiscussed in the background section, the hydrogen peroxide in bleach is a strong oxidising agent that is ableto convert some of the double bonds in chromophores to single bonds through redox reactions, removing thechromophore’s ability to display colour.

The sodium hyperchlorate and hydrogen peroxide in bleach can also liberate oxygen.

NaOCl + H2O2 O2 + NaCl + H2O

In this instance, the hydrogen peroxide acts as the reducing agent, and the oxygen that is produced from thereaction disturbs the stain particles and may dislodge them from the fibers of the fabric. One observationwas that the bleach slightly discoloured the stark white cotton fabric of the square that had no stain appliedto it. So the hydrogen peroxide even attacked the bright white chromophores in the fabric.

5.7 Lemon Juice

Lemon juice, in theory, should have been a very effective stain remover. However, it was only partiallyeffective on some of the stains and ineffective on the rest. Because lemon juice contains both lemon oil andwater, as well as acetic acid, it was soluble in water, oil, acid and base. However, the water-based lemonjuice was suspended in the oil, and the lemon oil was suspended in the base, so it was only partially solublein oil and base.

Lemon juice also slightly discoloured the fabric which is probably due to its yellow pigment being leftbehind on the fabric.

5.8 Tap Water

Although water is considered a universal solvent, because stains are made up of several constituents ofdifferent chemical nature, water cannot always remove the stain entirely. For example, foundation whichis made up of oils, pigments and opacifying agents which leave a heavy residue in the fibers of the fabric.The oils and chromophores that make up the pigment in foundation are non-polar and therefore cannot bedissolved in water. The particles of the opacifying agent were too heavy to be dislodged from the fabric by thewater molecules. Water did not have great impact on any of the stains when used entirely by itself. However,every other laundry detergent and cleaning solution was water-based - water was a necessary ingredient inall the other stain removal solutions.

5.9 Overall

It would seem from the results that baking soda was chemically similar to Drive. They both worked on thesame stains to a similar extent, however, their pH, conductivity, solubility and redox potential were different.So they are most likely not chemically similar, however, their chemical constituents work on similar parts ofthe same stains.

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It also seems that Sard Wonder Soap, OMO Liquid, Napisan Oxy-Action and bleach all have similarchemical constituents. As they all have redox potential and are soluble in bases, it is likely that Sard WonderSoap, OMO Liquid and Napisan Oxy-Action contain some form of bleach. However, Sard Wonder Soap wasmost likely the only laundry detergent that contained surfactants as it was the only stain remover that hada real effect on the foundation and ink stains.

Lemon juice and tap water were not very effective at removing any of the stains in the stain test. This isprobably because water only has the attribute of polar molecules that are only able to dissolve other polarmolecules, and lemon juice contains oil and citric acid which only allow it to dissolve oil-based and acidicstains.

All the stain removers except for lemon juice and tap water were able to effectively remove blood stains,which indicated the presence of phosphates. There were not any anomalous results.

The toughest stains are those that contained pigments, which only stain removers containing bleach orother oxidising agents were able to remove. Blood was able to be removed by stain removers that containedphosphates. Heavy, oil-based stains such as that of foundation and ink required surfactants (only present inSard Wonder Soap) in order to be removed.

Table 3: User’s guide to cleaning stainsStain Type Best CleanersCoffee Bleach, Napisan Oxy-ActionBeetroot Bleach, Napisan Oxy-ActionBlood Bleach, OMO LiquidGrass Bleach, Napisan Oxy-ActionRed Wine Bleach, Napisan Oxy-ActionFoundation Sard Wonder SoapBlack Ink Sard Wonder Soap

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6 Conclusion

The data collected from the five experiments in this extended experimental investigation were quite compre-hensive. This provided enough chemical information about the stain removal solutions to be able to drawconclusions about the chemical mechanisms of stain removal present throughout the investigation. However,there were some procedural inaccuracies that could have been further improved.

Warm water is sometimes required of laundry detergents in order for them to work properly. As discussedin the background section of this paper, an increase in temperature provides the molecules of both the stainand the cleaner with more energy, causing them to vibrate and move around more. By providing the particleswith more energy, redox reactions and dissolvation occurs more rapidly and is therefore more effective. Onlycold water was used during the investigation because the stains were left to soak for such a long period oftime, so it is possible that not all the laundry detergents worked to their full potential. An improvement tothe method of the stain experiment would have been to use warm or hot water instead of cold.

The concentrations of the stain removal solutions used in this investigation were not of the same concen-tration that would be used in a load of washing. This could have provided misleading results. However, theconcentrations were actually higher than if the were the true concentrations used in a load of washing. Ifthe results were affected in any way, they were only made clearer because the concentration would have beenhigh enough for the chemicals that did actually work on the stain to work to their full potential (disregardingtemperature), while the parts of the stain that could not be removed by the cleaner remained on the fabricat the end of the cleaning test.

This investigation could have been improved by testing a wider variety of cleaning solutions on morekinds of stains. Also, the presence of true enzymes (as opposed to oxidising agents) could be investigated.Further separation of the chemical constituents of the laundry detergents could be done in order to identifyparticular ingredients, their chemical properties, and role in stain removal.

Overall, the investigation provided accurate results that allowed the identification of different types ofstain removal solutions constituents and how they assisted in the removal of certain parts of different kindsof stains.

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References

[1] Calder, V. (2008) ”Stain Removal”, Ask A Scientist, Argonne National Laboratory,http://www.newton.dep.anl.gov/askasci/chem00/chem00229.htm (23/08/08)

[2] Calder, V. (2008) ”Ethanol as a Stain Remover”, Ask A Scientist, Argonne National Laboratory,http://www.newton.dep.anl.gov/askasci/chem07/chem07002.htm (23/08/08)

[3] Calder, V. (2008) ”Bonds and Stains on Fabrics”, Ask A Scientist, Argonne National Laboratory,http://www.newton.dep.anl.gov/askasci/chem03/chem03660.htm (23/08/08)

[4] Calder, V. (2008) ”Measuring Stain Intensity”, Ask A Scientist, Argonne National Laboratory,http://www.newton.dep.anl.gov/askasci/chem03/chem03813.htm (23/08/08)

[5] Calder, V. (2008) ”Phosphate and Stain Removal”, Ask A Scientist, Argonne National Laboratory,http://www.newton.dep.anl.gov/askasci/chem03/chem03735.htm (23/08/08)

[6] Cross, J. (2006) ”The makeup of the toughest stains”, CleanPros Online,http://www.cleanprosonline.com/Toughest stains.html (10/09/08)

[7] Donker, C.B. (1998) Non-aqueous Liquid Cleaning Products Which Contain Modified Silica, US Patentvol.5, no.714, pp.449.

[8] Moore, J. W. (1999) ”Redox Titration and Animation”, Chemistry ComesAlive, Division of Chemical Education, Inc., American Chemical Society.,http://jchemed.chem.wisc.edu/JCESoft/CCA/CCA3/MAIN/TITREDO/PAGE1.htm (01/09/08)

[9] Rainbow International (2007) ”Spot and Stain Removal Guide”, Rainbow International Restoration andCleaning, http://www.rainbowintl.com/expert/guide.aspx?c (10/09/08)

[10] Szczepanski, A. (2008) Personal correspondence.

[11] Wikipedia (2008) Micelle, Wikipedia, http://www.wikipedia.org/wiki/Micelle (23/08/08)

[12] Wikipedia (2008) Surfactant, Wikipedia, http://www.wikipedia.org/wiki/Surfactant (23/08/08)

[13] Wikipedia (2008) Redox Indicator, Wikipedia, http://www.wikipedia.org/wiki/RedoxIndicator(07/09/08

[14] Wikipedia (2008) Chromophore, Wikipedia, http://en.wikipedia.org/wiki/Chromophore (15/09/08)

[15] Wikipedia (2008) Bleach, Wikipedia, http://en.wikipedia.org/wiki/Bleach (15/09/08)

[16] Wikipedia (2008) Tannin, Wikipedia, http://en.wikipedia.org/wiki/Tannin (15/09/08)

[17] Wikipedia (2008) FeCO3, Wikipedia, http://en.wikipedia.org/wiki/Iron(II) carbonate (15/09/08)

[18] Yamada, I. (2003) The difference between anionic and nonionic surfactant, and its appliation to deter-gent, Chemistry Question, http://www.chemistryquestion.com (07/09/08)

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A Stain Removal Solutions’ Effectiveness on Different Stains

A.1 Aim

The aim of this experiment was to identify which stain removal solutions were able to remove which stainsand how effectively the stains were removed.

A.2 Equipment and Materials

• 64× 50mL beakers • 25mL Sard Wonder Soap• 25mL Tap water • 25mL Omo Liquid• 25mL Bleach • 25mL Drive• 25mL Baking soda • 25mL Napisan Oxy-action• 25mL Lemon juice • 64× 10cm×10cm white cotton squares• Coffee stain • Beetroot juice• Blood • Grass• Red Wine • Foundation• Black ink • Stirring rod

A.3 Procedure

1. Each of the stains (coffee, beetroot, blood, grass, red wine, foundation, black ink) were applied to 8pieces of white cotton each and left to dry for 24 hours.

2. 8 50mL beakers were filled with Sard Wonder Soap solution which was made by adding 1g of shavingsof the soap to 50mL of water in each beaker and stirring vigorously until all the soap was dissolved.

3. 8 50mL beakers were filled with baking soda solution which was made by dissolving 1g of baking sodain 50mL of tap water for each beaker.

4. 8 50mL beakers were filled with OMO Liquid solution which was made by adding 1mL of OMO Liquidto 50mL of tap water for each beaker.

5. 8 50mL beakers were filled with Drive solution which was made by adding 1g of laundry powder to50mL of warm tap water for each beaker. (warm water was only used to assist with dissolving thepowder in the water)

6. 8 50mL beakers were filled with Napisan Oxy-action solution which was made by adding 1g of laundrypowder to 50mL of warm tap water for each beaker. (warm water was only used to assist with dissolvingthe powder in the water)

7. 8 50mL beakers were filled with bleach solution which was made by adding 10mL of bleach to 50mLof tap water for each beaker.

8. 8 50mL beakers were filled with 50mL of lemon juice.

9. 8 50mL beakers were filled with 50mL of tap water.

10. Once all the solutions were of room temperature, one of each of the stains and the control (no stain)were added to the 8 beakers containing Sard Wonder Soap solution, making sure that the entire fabricsquare was submerged in the stain removal solution.

11. Step 10 was repeated for the other 7 stain removal solutions (including water) so that a grid of testbeakers was set up so each combination of stain and stain remover was tested.

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12. After the cotton squares were left to soak for 24 hours, they were rinsed in cold tap water.

A.4 Results

Table 4: Degree of stain removal (0 = no change, 5 = no trace)Coffee Beetroot Blood Grass Red Wine Foundation Ink None

Sard Wonder Soap 4 5 4 4 4 3 2 5Baking Soda 2 4 4 2 3 0 0 5OMO Liquid 4 4.5 4.5 4 4 1 2 5Drive 3 4.5 4 3 3 2 1 5Napisan Oxy-Action 4.5 5 4 4.5 4.5 1 0.5 5Bleach 5 5 5 5 5 0 0 4.5Lemon Juice 3 3 2 2 2 0 0 4.5Tap Water 3 3 3 1 3 0 0 5

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B Determining the pH of the Stain Removal Solutions

B.1 Aim

The aim of this experiment was to determine the pH of each of the stain removal solutions.

B.2 Equipment and Materials

• 8× 50mL beakers • 10mL Sard Wonder Soap solution• Distilled water • 10mL Omo Liquid solution• 10mL Tap water • 10mL Drive solution• 10mL Bleach solution • 10mL Napisan Oxy-action solution• 10mL Baking soda solution • Universal indicator• 10mL Lemon juice solution • Universal indicator pH colour chart

B.3 Procedure

1. Each if the stain removal solutions were prepared as in Experiment 1 (see Appendix A)

2. 10mL of each stain removal solution was poured into it’s own 50mL beaker.

3. The beakers were filled to the 20mL mark with distilled water.

4. 10 drops of universal indicator was added to each beaker.

5. The pH was identified by using the universal indicator pH colour chart to match the colour of thesolution in each beaker to the corresponding pH on the chart.

B.4 Results

Table 5: pH of Cleaning Solutions

Cleaning solution pHSard Wonder Soap 9Baking soda 8Omo Liquid 7Drive 11Napisan Oxy-action 10Bleach 8Lemon juice 4Tap water (control) 7

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C Conductivity of the Stain Removal Solutions

C.1 Aim

To determine the conductivity of the stain removal solutions.

C.2 Equipment and Materials

• 10× 50mL beakers • 25mL Sard Wonder Soap solution• Distilled water • 25mL Omo Liquid solution• Stirring rod • 25mL Drive solution• 25mL Tap water • 25mL Napisan Oxy-action solution• 25mL Bleach solution • 25mL 10% NaCl solution• 25mL Baking soda solution • Conductivity testing apparatus• 25mL Lemon juice solution • 100mL beaker

C.3 Procedure

1. A beaker containing 25mL of distilled water was placed in the conductivity testing apparatus so thatthe electrodes were submerged.

2. The brightness of the light bulb was noted. This set the marker for the least conductive solution.

3. The electrodes were rinsed off with distilled water into the 100mL beaker.

4. Steps 1-2 were repeated for the beaker containing 25mL of NaCl solution. This set the marker for themost conductive solution.

5. The conductivity of the 8 stain removal solutions (Sard Wonder Soap, baking soda, Omo Liquid, Drive,Napisan Oxy-action, bleach, lemon juice and tap water) was tested by comparing and rating the lightbulb’s brightness for each solution as an indicator of its conductivity.

C.4 Results

Table 6: Conductivity of Cleaning Solutions (0 = no conductivity, 5 = very high conductivity)

Cleaning solution ConductivityNaCl solution 5Distilled water 0Sard Wonder Soap 2Baking soda 5Omo Liquid 1Drive 3Napisan Oxy-action 4Bleach 4Lemon juice 4Tap water (control) 1

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D Solubility of the Stain Removal Solutions

D.1 Aim

To determine the solubility of the stain removal solutions in water, oil, acids and bases.

D.2 Equipment and Materials

• 32 test tubes • 20mL Omo Liquid solution• Test tube rack • 20mL Drive solution• Bamboo skewers • 20mL Napisan Oxy-action solution• Spatula • 80mL vegetable oil• 20mL Bleach solution • 80mL 0.1M HCl• 20mL Baking soda solution • 80mL 0.1M NaOH• 20mL Lemon juice solution • Tap water• 20mL Sard Wonder Soap solution

D.3 Procedure

1. 8 of the test tubes were filled with 10mL tap water each, 8 with vegetable oil, 8 with 0.1M HCl and 8with 0.1M NaOH.

2. 5mL of each of the stain removal solutions was added to each of the solvents so that a test grid wasmade so that each combination of stain removal solution and solvent was tested.

3. Each of the mixtures in the test tubes were stirred vigorously with a bamboo skewer, using a differentskewer in each test tube.

4. The test mixtures were left for 24hrs so that it was clear which solutions were dissolved and whichwere suspended.

D.4 Results

Table 7: Solubility of Cleaning Solutions

Cleaning solution Water Oil Acid BaseSard Wonder Soap X* X* × XBaking soda X × X XOmo Liquid X × X XDrive X × × XNapisan Oxy-action X × X XBleach X × X XLemon juice X X*1 X X*2

Tap water (control) X × X X

X = soluble, * = partially soluble, × = insoluble 1Water-based lemon juice was suspended 2Lemon oilwas suspended

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E Redox Indicator Test

E.1 Aim

The aim of this experiment was to identify the redox potential of each of the stain removal solutions.

E.2 Equipment and Materials

• 9× 50mL beakers • 25mL Sard Wonder Soap• Spatula • 25mL Omo Liquid• Stirring rods • 25mL Drive• 25mL Tap water • 25mL Napisan Oxy-action• 25mL Bleach • 25mL 0.1M Hydrogen Peroxide (H202)• 25mL Baking soda • 50mL 0.1M Hydrochloric Acid (HCl)• 25mL Lemon juice • 50mL Potassium Permanganate (KMnO4)

E.3 Procedure

1. The cleaning solutions were prepared as in Experiment 1 (see Appendix A).

2. 25mL of 0.1M Hydrogen Peroxide was added to the remaining 50mL beaker as the control.

3. Acidified potassium permanganate was made by mixing 50mL of 0.1M HCl with 50mL of KMnO4.

4. Even amounts of acidified potassium permanganate were added to each of the beakers containing thestain removal solutions as well as the control.

5. The solutions were observed over 30 minutes. The solutions that returned clear or to their originalcolour (ie. did not remain pink from the acidified potassium permanganate) were identified as havingundergone a redox reaction and therefore had redox potential.

E.4 Results

Table 8: Redox Potential Test

Cleaning solution Redox PotentialHydrogen Peroxide XSard Wonder Soap XBaking soda ×Omo Liquid XDrive XNapisan Oxy-action XBleach XLemon juice XTap water (control) ×

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