exp 6 soap detergent

8/19/2019 exp 6 soap detergent

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1.2 INTRODUCTION

1.3 OBJECTIVE

1. To prepare soap and compare its properties to that of a synthetics detergent.

1.4 THEORY

Soap is the salt of weak acid. Most organic acids are weak acids. Consequently,

hydrolysis occurs to some extent when soap dissolves in water. Soap solutions tent to e

slightly alkaline !asic" due to partial hydrolysis of the acid.

The cleansing action of soaps results from two effects. Soaps are wetting agents that

reduce the surface tension of water, allowing the water molecules to encounter the dirty

o#ect. They are also emulsifying agents. $%irt& frequently consists of a grease or oil

along with other organic species. 'n general, organic compounds are nonpolar. (ater is

a polar species. These two sustances will not dissolve in each other ecause of their

dissimilar characteristics !the $)ike %issolve )ike& rule". Soaps cross the oundary

etween polar and nonpolar ecause they contain a polar hydrophoic !water*hating"

end and a polar hydrophilic !water*loving" end.

+ecause soaps have oth polar and nonpolar region in the molecule, they are solule in

oth polar and nonpolar species. The hydrophoic !nonpolar" portion of soap is solule

in nonpolar compound like grease and oils. The hydrophilic !polar" end dissolves in

water. Soap molecules surround the grease and oils and reak them up into microscopic

droplets can remain suspended in water. These suspended microscopic droplets are

called micelles. Micelles contain very small amounts of oil or grease in their center. Thus



the oil or grease has een dissolved in water forming an emulsion, one form of a

suspension in water.

(ater supplies in certain areas are acidic as a result of acid rain or pollution, or $hard&

due to the dissolved mineral content. +oth acidic and $hard& water reduce the cleansing

action of soap. Soap is the salt of a weak acid. 'n the presence of a stronger acid, thesodium salt is converted to an insolule organic acid.

$ard water& contains dissolved Ca-, Mg- and /e0 ions from the minerals that the water

passes over. ormally, soaps made from sodium and potassium fatty acid salts are

solule in water. owever, in the presence of these metal ions, the a and 2 solule

salts convert to insolule Ca-, Mg- and /e0 salts.

'n either acidic or $hard& water, the solule soaps form insolule salts that ecomes a

scummy ring on athtus and lack areas on shirt collars. The cleansing aility of soap

is reduces ecause soap molecules are removed from the solution. There are several

techniques used to circumvent the prolems generated y hard water. (ater can e

$softened& via removing hard water ions from solution using ion exchange techniques or

y adding water softening agents, such as sodium phosphate !a0345" or sodium

caronate !a-C40". (ater softening agents react with the Ca-, Mg- and /e0 y

removing them from water and preventing the reaction of these ions with soap. Thus $Syndets& was design to overcome the soap prolem with $hard& water. Syndets

differ from soaps in that the nonpolar fatty acids groups are replaced with alkyl or aryl

sulfonic acids !64S40". The alkyl or aryl sulfonic acids have long chains of caron

atoms giving the hydrophoic !nonpolar" end. The salt of the sulfonic acid !sulfonate"

group forms the hydrophilic end of the molecule. The difference in polar groups is one of

the key distinctions etween soap and the synthetic detergent. Syndets from micelles

and cleanse in the same manner as soaps.

+ecause sulfonic acid is a stronger acid than caroxylic acids, Syndets do not precipitate

in acidic solutions. /urthermore, alkyl and aryl sulfonates do not form insolule salts in



the presence of the typical hard water ions. Thus, synthetic detergents remain solule in

oth acidic and $hard& water.

1.5 APPARATUS

7pparatus Materials

• -89 m) :rlenmeyer flask

• ;acuum filtration apparatus

• +eaker

• Test tues

• Cloth strips

• Measuring cylinder

• <lass rod

• p meter electronic

• ;egetale oil

• :thanol

• Sodium hydroxide

• Saturated sodium chloride !aCl"

• Synthetic detergent !%ynamo"

• Mineral oil

• 1= CaCl- solution

• 1= MgCl- solution

• 1= /eCl- solution

• Tomato sauce

• %istilled water

1.6 PROCEDURE !ETHODO"O#Y

1.>.1 Soap preparation

1. -8 m) of vegetale oil is placed in a -89 m) :rlenmeyer flask. -9 m) of ethanol and

-9 m) of >M sodium hydroxide solution are added to the flask. The mixture is stirred

with the stiring rod to mix the contents of the flask.-. The -89 m) flask is heated in a oiling ? water ath inside of a >99 m) eaker0. The mixture continuously stirred during the heating process to prevent the mixture

from foaming. The mixture should foam to the point of nearly overflowing, remove the

flask from the oiling ?water ath until the foaming susides, then continue heating.

eat the mixture for -9*09 minute or until the alcohol odor is no longer detectale.5. The paste*like mixture from the oiling water ath and the flask is cooled in an ice

ath for 19*18 minutes.8. The soap is take out from the :rlenmeyer flask and put it into filter paper. The soap is

pressed etween two filter paper to dry it. The filter paper and dried soap is weigh



and the mass is recorded o nearest 9.991 and the mass of the soap is determined y

difference and the mass is recorded.

1.>.- Comparison of soap and detergent properties! precipitation and emulsification"

1. 7 stock soap solution is prepared y dissolving -g of your prepared soap in

199m) of oiling distilled water. The mixture is stirred until the soap has dissolved

and the solution is allowed to cool.

-. Step 1 is repeated using - g of synthetic detergent !eg. %ynamo". (hen oth

solutions are cool, the p of each solution is determined using p paper.

0. Three test tues are laeled as test tue 1, - and 0. 5 drops of mineral oil are

added to each test tue. 8 m) of distilled water is added to test tue 1. 8 m) of

stock soap solution is added to test tue -. 8 m) of stock synthetic detergent is

added to test tue 0.

5. :ach solution is mixed y shaking and is let to stand for three to five minutes. The

solutions, if any, emulsifies the oil y forming a single layer are noted.

8. The mixtures are poured into the (aste Container. The three test tues are

cleaned and dried.

>. Three test tues are laeled as test tue 1, - and 0. - m) of stock soap solution

is placed in each of the three test tues. - m) of 1= CaCl- solution is added to

test tue 1. - m) of 1= MgCl- solution is added to test tue -. - m) of 1= /eCl-

solutions is added to test tue 0. :ach test tue is shaken to mix the solutions.

The oservation is recorded.

@. 5 drops of mineral oil are added to each of the test tues in step >. :ach test

tues are shaken to mix the solutions and the solutions are let to stand for three

five minutes. The solutions, if any, emulsifies the oil y forming a single layer are

noted.



A. Steps > ? @ are repeated using - m) of stock detergent solutions.

B. The solutions, if any, emulsifies the oil y forming a single layer are noted.

19. The mixture is poured into the (aste Container. The test tue is cleaned and

dried.

11. 8 m) of stock solutions and 8 m) of stock detergent solution are placed in a clean

test tue and in a second test tue respectively. 1 M Cl one drop is added at a

time to oth solutions until the p in each test tue is equal to -. !p paper is

used to measure". The numer of drops of acid added is counted to each mixture.

1-. 1 drop of mineral oil is added to each test tue in step 11. :ach test tue is

shaken to mix the solution.

1.>.0Comparison of the cleaning ailities of a soap and detergent

1. Three eakers are cleaned, dried and laeled. -9 m) of stock soap solution !from

step 1 in section 0.5.0." is placed in the 1st eaker. -9 m) of stock detergent

solution !from step - in section >.5.5" is placed in the - nd eaker. -9 m) of the

commercial liquid %ynamo is placed.

-. Three cloth test strips that have een soaked in tomato sauce are otained and

one strip is placed in each of the eakers. 4ne cloth strip is placed in eaker 1

!from aove", one cloth strip is placed in eaker -, and one cloth strip is placed in

eaker 0. The solution is stirred repeatedly with stirring rod for 8 minutes.

0. The cloth strips are removed from the soap and detergent solution and the

excess water is squeeed out. :ach cloth strip is compared visually to determine

their relative cleanliness. The oservation is recorded.

1.$ RESU"TS1.$.1 S%&' P(e'&(&)i%*



M!%% o9 2et#i "i%1 () 06.376

M!%% o9 2et#i "i%1 =

%o!2 ()

64.-4

M!%% o9 %o!2 #eo>e#e"

()

03.540

1.$.2 C%m'&(is%* %+ s%&' &*, De)e(-e*) '(%'e()ies

Tale of :mulsification

System :mulsification occurred

%istilled water o

Soap Des

%etergent Des

Tale of addition of ard water and 7cid

System3recipitate 4il emulsified

Soap %etergent Soap %etergent

CaCl-

Des!all ecome

whiteprecipitate"

oDes

!homogeneous"

Des!homogeneus"

MgCl-

Des!cloudnessprecipitate"

oDes

!homogeneus"Des

!homogeneus"

/eCl-

Des!yellow rown

precipitate"o

o!heterogeneus

"

Des!homogeneus"

+rand name of syntheticsdetergent

%ynamo

p of soap solution 1-

p of synthetics detergentsolution

A



7cidic !Cl"Des

!whiteprecipitate"

oo

!heterogeneus"

Des!homogeneus"

1.$.3 Cle&*si*- c%m'&(is%* %+ & s%&' s/*)0e)ics ,e)e(-e*)s &*, ,/*&m%.

System cleansing aility

Soap The dirtiest etween the three.

Synthetic detergents Clean compared to the soap.

%ynamo !pure without addition of water" The most clean compared to the soapand synthetic detergent.

6effer to the appendix for picture

1. CA"CU"ATIONS



1. DISCUSSIONS



1.1 CONC"USIONS

'n the experiment, we prepared soap y using the vegetales oil, ethanol and sodium

hydroxide that continuously stirred during heating process until only ules remain. 7fter

the process we manage to recover 0>.850 g of soap that having p value of 1-. The soap is

then, compared with the synthetic detergent !dynamo" for their cleansing aility. Throughout

the experiment, we conclude that the cleansing ailities of the soap that we prepared are

less effective than the synthetic detergent which is not leaving any precipitate after addition

of ard water and acid.

1.11 RECO!!ENDATIONS

1. (e must avoid from make a parallax error for most of the measured. /or example

when taking the reading from measuring cylinder or dropper caliration. This error

can e reduced y always ensuring that readings are always made at eye level and

that the same person taking the readings is constant as #udgment varies with each

person.

-. (e must take each measurement as sharply as possile so that the final result eing

etter.

0. This la could e improved y improving the method of drying volumetric flask and

eaker efore filling it with any solution that used in this experiment. The glassware

could e dried y small amount of acetone. 7ny acetone could e removed y

evaporation.

5. To get the etter result or weight of soap that can e recovered, all of the soap must

e dried and not eing waste even a little ecause it will affect the calculation in this

experiment.

1.12 REERENCES



1. +asic (ater 3roperties -, 3ulished y geek011-, date of pulishedE1-F19F-919,

6etrieved fromG httpGFFwww.scrid.comFdocF0B1>>-0-F+asic*(ater*3roperties*-*

:xperiment- . h t tp G F Fwww. f reed r i nk ingwa te r . comFwa te r *educa t i on Fqua l i t y *wa te r *

heavymea ta l .h tm0 . h t t p G F F ww w. h e al t h y * wa t e r * es t * f i lt e r s . c om F h e av y * m e ta l s * wi t h i n *

water .h tml5. httpGFFwater.me.vccs.eduFcoursesF:;15BFod.htm8 . h t tp G F Fwww. lenn tech .comFpe r i od i c Fwa te r F ch romiumFch romium*and *

water .h tm

>. httpGFFscience.howstuffworks.comFdictionaryFchemistry*termsFemulsion*info.htm

1.13 APPENDI

http://www.scribd.com/doc/39166232/Basic-Water-Properties-2-Experiment


http://water.me.vccs.edu/courses/ENV149/bod.htm

http://www.lenntech.com/periodic/water/chromium/chromium-and-water.htm


http://science.howstuffworks.com/dictionary/chemistry-terms/emulsion-info.htm

http://water.me.vccs.edu/courses/ENV149/bod.htm



http://science.howstuffworks.com/dictionary/chemistry-terms/emulsion-info.htm





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exp 6 soap detergent

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