Name:
Name: Jobel Jobel D. D. De De Pedro Pedro Date Date Performed:Performed: Group
Group #: #: 6 6 Date Date Submitted:Submitted: Experiment 9
Experiment 9
ACYL COMPOUNDS: SOAPS AND DETERGENTS ACYL COMPOUNDS: SOAPS AND DETERGENTS I. OBJECTIVES
I. OBJECTIVES 1.
1. To oTo observe the bserve the general properties general properties of of carboxylic acids.carboxylic acids. 2.
2. To compare To compare the the acidity of acidity of carboxylic acids carboxylic acids and and phenols.phenols. 3.
3. To verify To verify experimentalexperimentally ly the inthe interconversiterconversion on among among acyl compounds.acyl compounds. 4.
4. To become To become familiafamiliar with r with the physical and the physical and chemical properties of chemical properties of fats and fats and oils and oils and toto understand the chemical basis of these properties.
understand the chemical basis of these properties. 5.
5. To To learn learn how how to to prepare soap.prepare soap. 6.
6. To compare To compare the the properties of properties of soap soap and and synthetic detergents.synthetic detergents. II. THEORETICAL FRAMEWORK
II. THEORETICAL FRAMEWORK
Soap is an anionic surfactant used in conjunction with water for washing and cleaning Soap is an anionic surfactant used in conjunction with water for washing and cleaning that historically comes in solid bars but also in the form of a thick liquid. Soap, consisting of that historically comes in solid bars but also in the form of a thick liquid. Soap, consisting of sodium (soda ash) or potassium (potash) salts of fatty acids is obtained by reacting fat with lye sodium (soda ash) or potassium (potash) salts of fatty acids is obtained by reacting fat with lye in a process known as saponification. The fats are hydrolyzed by the base, yielding alkali salts in a process known as saponification. The fats are hydrolyzed by the base, yielding alkali salts of fatty acids (crude
of fatty acids (crude soap) and glycerol.soap) and glycerol.
Many cleaning agents today are technically not soaps, but detergents, which are less Many cleaning agents today are technically not soaps, but detergents, which are less expensive and easier to manufacture.
expensive and easier to manufacture.
Soaps are useful for cleaning because soap molecules attach readily to both nonpolar Soaps are useful for cleaning because soap molecules attach readily to both nonpolar molecules (such as grease or oil) and polar molecules (such as water). Although grease will molecules (such as grease or oil) and polar molecules (such as water). Although grease will normally adhere to skin or clothing, the soap molecules can attach to it as a "handle" and make normally adhere to skin or clothing, the soap molecules can attach to it as a "handle" and make it easier to rinse away. Applied to a siled surface, soapy water effectively holds particles in it easier to rinse away. Applied to a siled surface, soapy water effectively holds particles in suspension so the whole of it can be rinsed off with clean water.
suspension so the whole of it can be rinsed off with clean water. (Fatty end):CH
(Fatty end):CH33-(CH-(CH22))nn - COONa: (water soluble end)- COONa: (water soluble end)
The hydrocarbon ("fatty") portion dissolves dirt and oils, while the ionic end makes it The hydrocarbon ("fatty") portion dissolves dirt and oils, while the ionic end makes it soluble in water. Therefore, it allows water to remove normally-insoluble matter by emulsification. soluble in water. Therefore, it allows water to remove normally-insoluble matter by emulsification. The most popular soapmaking process today is the cold process method, where fats The most popular soapmaking process today is the cold process method, where fats such as olive oil react with lye, while some soapers use the historical hot process.
such as olive oil react with lye, while some soapers use the historical hot process.
Handmade soap differs from industrial soap in that, usually, an excess of fat is Handmade soap differs from industrial soap in that, usually, an excess of fat is sometimes used to consume the alkali (
sometimes used to consume the alkali ( superfatting superfatting ), and in that the glycerin is not removed), and in that the glycerin is not removed leaving a naturally moisturising soap and not pure detergent. Superfatted soap, soap which leaving a naturally moisturising soap and not pure detergent. Superfatted soap, soap which contains excess fat, is more skin-friendly than industrial soap, though if too much fat is added it contains excess fat, is more skin-friendly than industrial soap, though if too much fat is added it can leave users with a "greasy" feel to their skin. Often, emollients such as jojoba oil or shea can leave users with a "greasy" feel to their skin. Often, emollients such as jojoba oil or shea butter are added 'at trace' (the point at which the saponification process is sufficiently advanced butter are added 'at trace' (the point at which the saponification process is sufficiently advanced that the soap has begun to thicken), after most of the oils have saponified, so that they remain that the soap has begun to thicken), after most of the oils have saponified, so that they remain unreacted in the finished soap. Superfatting can also be accomplished through a process called unreacted in the finished soap. Superfatting can also be accomplished through a process called superfat discount, where, instead of putting in extra fats, the soap maker puts in less lye.
III. DATA AND RESULTS III. DATA AND RESULTS
Table 1. Solubility and acidity of Carboxylic acids Table 1. Solubility and acidity of Carboxylic acids
SAMPLE
SAMPLE WAWATER TER SOLUBILITYSOLUBILITY RXN TO LITMUS PAPER TESTRXN TO LITMUS PAPER TEST Acetic acid
Acetic acid SolubleSoluble Acidic: turns blue LP to Acidic: turns blue LP to redred Benzoic acid
Benzoic acid InsolubleInsoluble Acidic: turns blue LP to Acidic: turns blue LP to redred Sodium benzoate
Sodium benzoate SolubleSoluble Basic: no change in blue LPBasic: no change in blue LP Table 2. Relative acidities of Carboxylic acids and Phenols
Table 2. Relative acidities of Carboxylic acids and Phenols SAMPLE
SAMPLE Solubility in 10% NaOHSolubility in 10% NaOH Solubility in 10% NaHCOSolubility in 10% NaHCO33
Phenol
Phenol SolubleSoluble SolubleSoluble
Benzoic acid
Benzoic acid SolubleSoluble InsolubleInsoluble
Table 3. Observations upon addition of water and heating the samples, as well as their Table 3. Observations upon addition of water and heating the samples, as well as their reactions to litmus paper test
reactions to litmus paper test.. SAMPLE
SAMPLE RXN SIGNSRXN SIGNS WATER BATHWATER BATH
Acetyl Chloride
Acetyl Chloride Heat; semi-cloudy; bubble formationHeat; semi-cloudy; bubble formation No changeNo change Acetic anhydride
Acetic anhydride Clear, homogeneous solutionClear, homogeneous solution No changeNo change Benzamide
Benzamide InsolubleInsoluble Dissolved, clear solutionDissolved, clear solution Table 4. Comparison of Soaps and Detergents
Table 4. Comparison of Soaps and Detergents SOAP
SOAP DETERGENTDETERGENT
Hydrolysis
Hydrolysis Cloudy, basicCloudy, basic Clear, basicClear, basic Rxn with Acid
Rxn with Acid TurbidTurbid Clear Clear
Rxn with Soft Water
Rxn with Soft Water TurbidTurbid Clear Clear
Rxn with Hard Water
Rxn with Hard Water Formation of scumsFormation of scums Turbid, no scumsTurbid, no scums Emulsifying Action
Emulsifying Action Formation of smaller bubblesFormation of smaller bubbles More bubbles were formedMore bubbles were formed IV. DISCUSSION
IV. DISCUSSION
Solubility and Acidity of Carboxylic Acids Solubility and Acidity of Carboxylic Acids
For table 1, Acetic acid and sodium benzoate were both soluble in water while benzoic For table 1, Acetic acid and sodium benzoate were both soluble in water while benzoic acid was not. Unlike aldehydes and ketones, instead of protonation to be undergone to yield an acid was not. Unlike aldehydes and ketones, instead of protonation to be undergone to yield an alcohol, the initially formed alkoxide intermediate expels one of the substituents originally alcohol, the initially formed alkoxide intermediate expels one of the substituents originally bonded to the carbonyl carbon, leading to the formation of a new carbonyl compound by a bonded to the carbonyl carbon, leading to the formation of a new carbonyl compound by a nucleophilic acyl substitution reaction.
nucleophilic acyl substitution reaction.
The different behavior towards nucleophiles of carboxylic acids derivatives is a The different behavior towards nucleophiles of carboxylic acids derivatives is a consequence of structure. In the case of benzoic acid, the C=O carbon is electron-rich making consequence of structure. In the case of benzoic acid, the C=O carbon is electron-rich making the compound less ready to react with water, a nucleophile. The more electron-poor the C=O the compound less ready to react with water, a nucleophile. The more electron-poor the C=O carbon, the more readily the compound reacts with nucleophiles. This is why acetic acid and carbon, the more readily the compound reacts with nucleophiles. This is why acetic acid and sodium benzoate were able to dissolve in water.
sodium benzoate were able to dissolve in water.
In table 2, both phenol and benzoic acid were soluble in 10% NaOH and were both In table 2, both phenol and benzoic acid were soluble in 10% NaOH and were both insoluble in 10% NaHCO
insoluble in 10% NaHCO3.3.Because acid dissociation is an equilibrium process, anything thatBecause acid dissociation is an equilibrium process, anything that
stabilizes the carboxylate ion favors increased dissociation and increased acidity. Phenols and stabilizes the carboxylate ion favors increased dissociation and increased acidity. Phenols and carboxylic acids are much more acidic than alcohols. In fact, some nitro-substituted phenols carboxylic acids are much more acidic than alcohols. In fact, some nitro-substituted phenols
even approach or surpass the acidity of carboxylic acids. One practical consequence of their even approach or surpass the acidity of carboxylic acids. One practical consequence of their acidity is that phenols and carboxylic acids are soluble in dilute aqueous NaOH but remain acidity is that phenols and carboxylic acids are soluble in dilute aqueous NaOH but remain undissolved in NaHCO
undissolved in NaHCO33..
Hydrolysis of Acyl Compounds Hydrolysis of Acyl Compounds
Acyl compounds differ in their reactivities toward nucleophilic acyl substitution and this is Acyl compounds differ in their reactivities toward nucleophilic acyl substitution and this is evident from their hydrolysis reactions. Hydrolysis is a chemical reaction in which compound is evident from their hydrolysis reactions. Hydrolysis is a chemical reaction in which compound is broken down by reaction with water.
broken down by reaction with water. Acid halides are among the most reactive of the variousAcid halides are among the most reactive of the various carboxylic acid derivatives and can be converted into many other kinds of substances. The carboxylic acid derivatives and can be converted into many other kinds of substances. The halogen can be replaced by the ±OH to yield an acid, by ±OR to yield an ester or by ±NH halogen can be replaced by the ±OH to yield an acid, by ±OR to yield an ester or by ±NH 22 toto
yield an amide. The table below shows the different observations upon addition of water and yield an amide. The table below shows the different observations upon addition of water and heating the samples, as well as their reactions to litmus paper test.
heating the samples, as well as their reactions to litmus paper test.
Acetyl chloride, an acid chloride, was the first sample to react with water to yield Acetyl chloride, an acid chloride, was the first sample to react with water to yield carboxylic acids by the substitution of ±Cl by ±OH.
carboxylic acids by the substitution of ±Cl by ±OH.
The chemistry of acid anhydrides is similar to that of acid chlorides. Thus, results The chemistry of acid anhydrides is similar to that of acid chlorides. Thus, results showed that acetic anhydride reacted with water to form acids, after heating. The ease of which showed that acetic anhydride reacted with water to form acids, after heating. The ease of which the leaving group is lost depends upon its basicity: the weaker the base, the better the leaving the leaving group is lost depends upon its basicity: the weaker the base, the better the leaving group. For acid and anhydrides, the leaving group is the very weak base Cl- and CH3 group. For acid and anhydrides, the leaving group is the very weak base Cl- and CH3 respectively.
respectively.
Benzamide, an amide, is less reactive than acid chlorides and acid anhydrides. Amides Benzamide, an amide, is less reactive than acid chlorides and acid anhydrides. Amides undergo hydrolysis to yield carboxylic acids plus amine on heating in either aqueous acid or undergo hydrolysis to yield carboxylic acids plus amine on heating in either aqueous acid or base. Although the reaction is slow and requires prolonged heating, the overall transformation is base. Although the reaction is slow and requires prolonged heating, the overall transformation is a typical nucleophilic acyl substitution of ±OH for ±NH2.
a typical nucleophilic acyl substitution of ±OH for ±NH2. Saponification of Coconut Oil
Saponification of Coconut Oil
Triglycedrides are tri-esters of glycerol. They are the
Triglycedrides are tri-esters of glycerol. They are the most naturally occurrimost naturally occurring fats andng fats and oils. Alkaline hydrolysis of the three-ester linkages can break down triglycerides into their oils. Alkaline hydrolysis of the three-ester linkages can break down triglycerides into their
component parts and yield long-chain carboxylate salts and glycerol. The hydrolysis of fats and component parts and yield long-chain carboxylate salts and glycerol. The hydrolysis of fats and oil (coconut oil, in this experiment) in a basic medium is commonly called saponification and the oil (coconut oil, in this experiment) in a basic medium is commonly called saponification and the sodium salts produced are called soaps. Coconut oil is a source of lauric acid (12 carbons) sodium salts produced are called soaps. Coconut oil is a source of lauric acid (12 carbons) which can be made into sodium laurate.
which can be made into sodium laurate. Comparison of Soaps and Detergents Comparison of Soaps and Detergents
Soaps and detergents are similar in their general structure and properties, but different Soaps and detergents are similar in their general structure and properties, but different in their composition and some specific properties. This was apparent their hydrolysis reactions, in their composition and some specific properties. This was apparent their hydrolysis reactions, ability to react with mineral acids behavior in ³soft´ and ³hard´ water, and emulsifying properties ability to react with mineral acids behavior in ³soft´ and ³hard´ water, and emulsifying properties were studied. Table 4 shows the results of the experiment.
were studied. Table 4 shows the results of the experiment.
Soap from triacylglycerols is a mixture of long chain carboxylate salts. Detergents, on the other Soap from triacylglycerols is a mixture of long chain carboxylate salts. Detergents, on the other hand, are amphiphatic and are generally characterized by the presence of a sulfonate group. It hand, are amphiphatic and are generally characterized by the presence of a sulfonate group. It is a cleansing substance that acts similarly to soap but is made from chemical compounds is a cleansing substance that acts similarly to soap but is made from chemical compounds rather than fats and lye.
rather than fats and lye.
Soaps are the sodium salts of fatty acids. They are water soluble but the fatty acids Soaps are the sodium salts of fatty acids. They are water soluble but the fatty acids themselves are not. Soap can be converted into the fatty acid by means of a reaction with a themselves are not. Soap can be converted into the fatty acid by means of a reaction with a strong mineral (non-organic) acid. Acidification of detergents, on the other hand, produces acids strong mineral (non-organic) acid. Acidification of detergents, on the other hand, produces acids which are often water soluble. Because of this, soaps are ineffective in acidic water.
which are often water soluble. Because of this, soaps are ineffective in acidic water.
Although soap is a good cleaning agent, its effectiveness is reduced when used in hard Although soap is a good cleaning agent, its effectiveness is reduced when used in hard water. Hardness in water is caused by the presence of mineral salts such as calcium and water. Hardness in water is caused by the presence of mineral salts such as calcium and magnesium as well as iron and manganese. Soaps react with metal ions in the water to form magnesium as well as iron and manganese. Soaps react with metal ions in the water to form insoluble precipitates. The precipitates can be seen in the soapy water and are referred to as insoluble precipitates. The precipitates can be seen in the soapy water and are referred to as
³soap scum´. Unlike soaps, though, sulfonate in detergents does not form precipitates with the ³soap scum´. Unlike soaps, though, sulfonate in detergents does not form precipitates with the metal ions of hard water, reducing the discoloration of clothes due to the precipitated soap. metal ions of hard water, reducing the discoloration of clothes due to the precipitated soap.
V. CALCULATION V. CALCULATION
VI. ANSWERS TO QUESTIONS VI. ANSWERS TO QUESTIONS 1.
1. Explain the difference iExplain the difference in the n the solubility of solubility of benzoic acid and benzoic acid and sodium sodium benzoate in water.benzoate in water. Which of the two would you predict to be more soluble in CHCl
Which of the two would you predict to be more soluble in CHCl33? Explain.? Explain.
The different behavior towards nucleophiles of carboxylic acids derivatives is a The different behavior towards nucleophiles of carboxylic acids derivatives is a consequence of structure. In the case of benzoic acid, the C=O carbon is electron rich consequence of structure. In the case of benzoic acid, the C=O carbon is electron rich making the compound less ready to react with water, a nucleophile. The more electron-poor making the compound less ready to react with water, a nucleophile. The more electron-poor the C=O carbon, the more readily the compound reacts with nucleophiles. When placed in the C=O carbon, the more readily the compound reacts with nucleophiles. When placed in water, sodium benzoate dissociates to form sodium ions and benzoic acid ions. It is a weak water, sodium benzoate dissociates to form sodium ions and benzoic acid ions. It is a weak organic acid that contains a carboxyl group. This accounts for the higher solubility of sodium organic acid that contains a carboxyl group. This accounts for the higher solubility of sodium benzoate in water.
benzoate in water. 2.
2. Based on the results Based on the results in Part A.2, what can in Part A.2, what can be said about the relative be said about the relative acidities of acidities of phenols and
phenols and carboxylic acids? carboxylic acids? Arrange the Arrange the following compound types following compound types in order of in order of increasing acidity:
increasing acidity: carboxylic acid, carboxylic acid, alcohol, phenol alcohol, phenol and water.and water.
Carboxylic acids are much more acidic than alcohols even though both contain O²H Carboxylic acids are much more acidic than alcohols even though both contain O²H group due to the relative stabilities of carboxylate anions versus alkoxide anions. In an group due to the relative stabilities of carboxylate anions versus alkoxide anions. In an alkoxide ion, the negative charge is localized on one oxygen atom. In carboxylate ion, alkoxide ion, the negative charge is localized on one oxygen atom. In carboxylate ion, however, the negative charge is delocalized, or spread out over both oxygen atoms. In other however, the negative charge is delocalized, or spread out over both oxygen atoms. In other words, a carboxylate ion is a stabilized resonance hybrid of two equivalent structures.
words, a carboxylate ion is a stabilized resonance hybrid of two equivalent structures.
Phenols, on the other hand, are more acidic than alcohols because the phenoxide anion Phenols, on the other hand, are more acidic than alcohols because the phenoxide anion is resonance-stabilized by the aromatic ring. Sharing the negative charge over the ring is resonance-stabilized by the aromatic ring. Sharing the negative charge over the ring increases the stability of the phenoxide anion and thus increases the tendency of the increases the stability of the phenoxide anion and thus increases the tendency of the corresponding phenol to dissociate. Therefore, carboxylic acids > phenols > alcohols in corresponding phenol to dissociate. Therefore, carboxylic acids > phenols > alcohols in terms of their acidities.
terms of their acidities. 3.
3. Based on the results Based on the results in Part B, in Part B, arrange the following compound types in arrange the following compound types in the order of the order of decreasing hydrolysis rate: acid
decreasing hydrolysis rate: acid halides, acid anhydrides, esters, halides, acid anhydrides, esters, and amides. and amides. GiveGive the theoretical explanations for the observed differences in reaction rates.
the theoretical explanations for the observed differences in reaction rates.
The more highly polar a compound is, the more reactive it is. As confirmed by the The more highly polar a compound is, the more reactive it is. As confirmed by the results of the experiment, the polar acid halides are the most reactive of the carboxylic acid results of the experiment, the polar acid halides are the most reactive of the carboxylic acid derivatives because the electronegative halide atom strongly polarizes the carbonyl group. derivatives because the electronegative halide atom strongly polarizes the carbonyl group. Acid anhydrides react in almost the same manner as acid halides, although at a slower rate. Acid anhydrides react in almost the same manner as acid halides, although at a slower rate. Only ³half´ of the anhydride molecule is used. The other half acts as the leaving group Only ³half´ of the anhydride molecule is used. The other half acts as the leaving group during the nucleophilic acyl substitution step and produces carboxylate anion as a during the nucleophilic acyl substitution step and produces carboxylate anion as a by-product. Thus, anhydrides are inefficient to use, and acid chlorides are normally preferred product. Thus, anhydrides are inefficient to use, and acid chlorides are normally preferred for introducing acyl substituents other than acetyl groups. Esters show the same kinds of for introducing acyl substituents other than acetyl groups. Esters show the same kinds of chemistry as the first two compounds mentioned, but are less reactive toward nucleophiles chemistry as the first two compounds mentioned, but are less reactive toward nucleophiles than acid chlorides or anhydrides. The slowest to hydrolyze are the amides since their than acid chlorides or anhydrides. The slowest to hydrolyze are the amides since their linkage is very stable and is enough to serve as the basic unit from which proteins are made. linkage is very stable and is enough to serve as the basic unit from which proteins are made.
4.
4. The soap wThe soap water mixture a ater mixture a true solution? true solution? Cite examples to Cite examples to support your answer.support your answer.
A soap solution is not a real solution but a colloidal mixture that aroused after the A soap solution is not a real solution but a colloidal mixture that aroused after the addition of soap to water. It is considered a colloid, a cloudy mixture where one substance addition of soap to water. It is considered a colloid, a cloudy mixture where one substance is dispersed evenly throughout another. Because of this effective dispersal, some colloids is dispersed evenly throughout another. Because of this effective dispersal, some colloids have are mistaken to be solutions since they have similar appearances.
have are mistaken to be solutions since they have similar appearances. 5.
5. What is What is a colloidal ma colloidal mixture? ixture? How does How does a colloidal a colloidal mixture arise wmixture arise when soap hen soap is is mixedmixed with water?
with water?
A colloid or colloidal dispersion is a substance with components of one or two A colloid or colloidal dispersion is a substance with components of one or two phases. It is a heterogeneous mixture where very small particles of one substance are phases. It is a heterogeneous mixture where very small particles of one substance are distributed evenly throughout another substance. A colloidal mixture has an outer layer of distributed evenly throughout another substance. A colloidal mixture has an outer layer of ions with the same charge so that these repel each other. This results to lesser aggregation ions with the same charge so that these repel each other. This results to lesser aggregation to form particles that are large enough to precipitate.
to form particles that are large enough to precipitate.
Oil is a pure hydrocarbon so it is non-polar. The non-polar hydrocarbon tail of the Oil is a pure hydrocarbon so it is non-polar. The non-polar hydrocarbon tail of the soap dissolves into the oil. That leaves the polar carboxylate ion of the soap molecules soap dissolves into the oil. That leaves the polar carboxylate ion of the soap molecules sticking out of the oil droplets. These spherical clusters, called micelles, which surfaces are sticking out of the oil droplets. These spherical clusters, called micelles, which surfaces are negatively charged is where droplets of grease or oil are solubilized in water. Then, they negatively charged is where droplets of grease or oil are solubilized in water. Then, they become coated by the hydrophobic non-polar tails of soap molecules. As a result, the oil become coated by the hydrophobic non-polar tails of soap molecules. As a result, the oil droplets repel each other and remain suspended in solution to be washed away by a stream droplets repel each other and remain suspended in solution to be washed away by a stream of water.
of water. 6.
6. On the basis On the basis of the litmof the litmus test, are the us test, are the soap-water and detergent-water mixturessoap-water and detergent-water mixtures acidic, basic or neutral?
acidic, basic or neutral? Explain the difference, if any Explain the difference, if any in the reactions of in the reactions of the soap-the soap-water and detergent-soap-water mixtures to litmus paper.
water and detergent-water mixtures to litmus paper.
Reaction with litmus paper shows the alkalinity of both soap-water and Reaction with litmus paper shows the alkalinity of both soap-water and detergent-water mixtures. Soaps undergo a hydrolysis reaction upon hydration and as a result, they water mixtures. Soaps undergo a hydrolysis reaction upon hydration and as a result, they tend to be alkaline. Detergent-water mixtures are also alkaline but in a lesser degree.
tend to be alkaline. Detergent-water mixtures are also alkaline but in a lesser degree. 7.
7. Which would yWhich would you predict to have ou predict to have a greater emula greater emulsifying power in sifying power in ³hard water´, soaps³hard water´, soaps or synthetic detergent? Explain.
or synthetic detergent? Explain.
Synthetic detergents have greater emulsifying in ³hard water´ because of the Synthetic detergents have greater emulsifying in ³hard water´ because of the presence of the sulfonate group in detergents. The sulfonate group doesn¶t react with the presence of the sulfonate group in detergents. The sulfonate group doesn¶t react with the calcium and magnesium ions in hard water to form films or scums, a property typical of calcium and magnesium ions in hard water to form films or scums, a property typical of soaps.
soaps. 8.
8. Explain the Explain the cleaning property of scleaning property of soaps and oaps and detergents based on detergents based on your observations of your observations of their emulsifying action.
their emulsifying action.
The cleaning action of both soaps and detergents results from their ability to emulsify The cleaning action of both soaps and detergents results from their ability to emulsify or disperse water-insoluble materials (dirt, oil, grease, etc.) and hold them in suspension in or disperse water-insoluble materials (dirt, oil, grease, etc.) and hold them in suspension in water. This ability comes from the molecular structure of soaps and detergents. When a water. This ability comes from the molecular structure of soaps and detergents. When a soap or detergent is added to water that contains oil or other water-insoluble materials, the soap or detergent is added to water that contains oil or other water-insoluble materials, the soap or detergent molecules surround the oil droplets. The oil or
soap or detergent molecules surround the oil droplets. The oil or grease is ³dissolved´ in thegrease is ³dissolved´ in the alkyl groups of the soap molecules while the ionic end
alkyl groups of the soap molecules while the ionic end allows the micelle to dissolve in allows the micelle to dissolve in water.water. As a
As a result, the oil droplets are dispersed throughout the water, as emulsification takes place,result, the oil droplets are dispersed throughout the water, as emulsification takes place, and can be rinsed away.
