11.1 Oil, water, and dish soap (polarity and emulsions)
UMassAmherstDepartmentofChemistry
LectureDemonstrations
11.1Oil,water,anddishsoap(IntermolecularforcesI) Subjects:Propertiesofliquids,intermolecularforces Description:Cookingoilandwaterareusedtoillustratethatpolarandnon-polar substancesdonotmix.Whendishsoapisadded,anemulsioniscreatedbyallowing thedispersionofoilintowater. Materials: Cookingoil Water(optional:addfoodcoloringtomakeitmorevisible) Dishwashingsoap 2500mLErlenmeyerflaskswithstoppers Procedure: Note:Usethedemocameratodisplaytheprocedure. 1.Pourwaterandoilintooneflask.Observehowtheoil"floats"ontopofthewater andthattheydon'tmixspontaneously. 2.Stopperandagitatetocreateanemulsion.Letthemixturestandandwithinafew moments,thelayerswillseparate. 3.Addoil,wateranddishsoaptothesecondflask. 4.Shaketheflasktomixthecontents.Inthepresenceoftheemulsifier,theemulsion willpersist. Discussion: "Likedissolveslike".Waterandethanolwillmixtoformahomogenousmixture,but oilandwaterdonot.Bothwaterandethanolarepolarmolecules.Theymixbecause oftheabilityoftheirdipolestointeract.Theenergyofattractionbetweenthetwo moleculesisenoughtoovercometheenergyexpendedinmixing.Oilisnon-polar andthusthereisnoattractionbetweenthetwomolecules. Anemulsionisadispersionofoneliquidintoanother.Anemulsifyingagentisadded toattainstabilityoftheemulsion.Someexamplesofemulsionsarehomogenized milk,butter,mayonnaise,andgravy.Inmayonnaisetheeggyolkistheemulsifier andingravyflouristheemulsifierthatallowsthewaterandthefattomix.Inthis demonstration,thedishsoapistheemulsifyingagent.Theemulsifyingactionof soapallowsgreaseandoiltoberemovedfromobjectsbeingcleaned. Safety:None Disposal:Solutionscanbepoureddownthedrain. References: 1.B.Z.Shakhashiri;ChemicalDemonstrations:AHandbookforTeachersofChemistry; Volume3;Wisconsin;1989;p.351-352 2.NCSUChemistryDepartmentLecturedemonstrationwebsite:
1
UMassAmherstDepartmentofChemistry
LectureDemonstrations
2
................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related download
- lemon vitality young living
- if mixing is urgent—try detergent
- 11 1 oil water and dish soap polarity and emulsions
- tracking pollution a hazardous whodunit june 2004
- fluids how thick are liquids stanford university
- science experiment seven layer density column
- lava lamp american chemical society
- lesson plan 17 diy lava lamp
- soils clean and capture water
Related searches
- recipe for dawn dish soap and vinegar
- dawn dish soap and vinegar cleaner ratio
- dawn dish soap and white vinegar cleaner
- oil water and detergent experiment
- dawn dish soap hydrogen peroxide
- dawn dish soap and vinegar
- dawn dish soap website
- dish soap and peroxide experiment
- dish soap spray for bugs
- dawn dish soap and peroxide
- dawn dish soap as pesticide
- dawn dish soap sds