8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
1/22
KENDRIYA VIDYALAYA
JANAKPURI
SESSION : 2016-17
INVESTIGATORY PROJECT-
EVAPORATION OF LIQUID
Name : DIVYANSU
R!"" N!# : 17
C"a$$ : %II
Se&'(!) : A
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
2/22
CERTIFICATE
This is to certify that Divyanshu of
Class XII ‘A’ has satisfactorily completed the
project on “ EVAPORATION OF LIQUID” under
the guidance of M!"#M $%MA& "'T(
Chemistry during the session)*+,(+-!
"lace. $!/!0ana1puri "#M $%MA
Date. "'T(Chemistry
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
3/22
ACKNO*LEDGE+ENT
I2d li1e to e3press my greatest gratitude to the people 4ho have helped 5supported me
throughout my project! I’ m grateful to +R#
PRE+ KU+AR, PGT-Cem($'./ for his
continuous support for the project& from initial
advice 5 encouragement to this day!
6pecial than1s of mine goes to my colleague
4ho helped me in completing the project 7y
giving interesting ideas& thoughts 5 made this
project easy and accurate!I 4ish to than1s my parents for their
undivided support 5 interest 4ho inspired me
5 encouraged me to go my o4n 4ay& 4ithout
4hich I 4ould 7e una7le to complete my
project! At last 7ut not the least I 4ant to
than1s my friends 4ho appreciated me for my
4or1 5 motivated me and finally to 'od 4ho
made all the things possi7le!!!
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
4/22
CONTENTS
6! no! Contents "age 8o!
+ I8T9D%CTI98 +
) AIM :; A""AAT%6 <
: MAT#IA= #>%I#D ,
< T?#9@ -
, "9C#D%# +;
- "?9T9'A"? +<
9B6#/ATI98 +,
C98C=%6I98 +-
+* BIB=I9'A"?@ +
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
5/22
INTRODUCTION
#vaporation is the process 4here7y atoms
or molecules in a liuid state Eor solid state
if the su7stance su7limesF gain sufficient
energy to enter the gaseous state!
The thermal motion of a molecule must 7e
sufficient to overcome the surface tension
of the liuid in order for it to evaporate&
that is& its 1inetic energy must e3ceed the
4or1 function of cohesion at the surface!
#vaporation therefore proceeds more
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
6/22
uic1ly at higher temperature and in
liuids 4ith lo4er surface tension! 6ince
only a small proportion of the molecules
are located near the surface and are
moving in the proper direction to escape at
any given instant& the rate of evaporation is
limited! Also& as the faster(moving
molecules escape& the remaining molecules
have lo4er average 1inetic energy& and the
temperature of the liuid thus decreases!
If the evaporation ta1es place in a closed
vessel& the escaping molecules accumulate
as a vapor a7ove the liuid! Many of the
molecules return to the liuid& 4ith
returning molecules 7ecoming more
freuent as the density and pressure of the
vapor increases! Ghen the process of
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
7/22
escape and return reaches euili7rium& the
vapor is said to 7e Hsaturated&H and no
further change in either vapor pressure and
density or liuid temperature 4ill occur!
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
8/22
Aim
To compare the rate of evaporation of
various liuids!
Apparatus
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
9/22
1. China dish
2. "ipette E +* ml F
# Geighing machine
Materials Required
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
10/22
+! ; different liuid samples
EAcetone&Gater&Diethyl ether are ta1en
hereF
Theory
Factors influencing rate of evaporation:-
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
11/22
+! Concentration of the su7stance
evaporating in the air! If the air already has
a high concentration of the su7stance
evaporating& then the given su7stance 4ill
evaporate more slo4ly!
)! Concentration of other su7stances in the
air! If the air is already saturated 4ith other
su7stances& it can have a lo4er capacity for
the su7stance evaporating!
;! Temperature of the su7stance! If the
su7stance is hotter& then evaporation 4ill
7e faster!
:! lo4 rate of air! This is in part related to
the concentration points a7ove! If fresh airis moving over the su7stance all the time&
then the concentration of the su7stance in
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
12/22
the air is less li1ely to go up 4ith time&
thus encouraging faster evaporation! In
addition& molecules in motion have more
energy than those at rest& and so the
stronger the flo4 of air& the greater the
evaporating po4er of the air molecules!
forces 1eeping the molecules together in
the liuid or solid state the more energy
that must 7e input in order to evaporate
them!
6# S.a&e a.ea a)3 'em4e.a'.e:
-Because molecules or atoms evaporate
from a liuid’6 surface& a larger surface
area allo4s more molecules or atoms to
leave the liuid& and evaporation occurs
more uic1ly! or e3ample& the same
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
13/22
amount of 4ater 4ill evaporate faster if
spilled on a ta7le than if it is left in a cup!
?igher temperatures also increase the rate
of evaporation! At higher temperatures&
molecules or atoms have a higher average
speed& and more particles are a7le to 7rea1
free of the liuid’6 surface! or e3ample& a
4et street 4ill dry faster in the hot sun
than in the shade!
ntermolecular forces: -
Most liuids are made up of molecules&
and the levels of mutual attraction among
different molecules help e3plain 4hy some
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
14/22
liuids evaporate faster than others!
Attractions 7et4een molecules arise
7ecause molecules typically have regions
that carry a slight negative charge& and
other regions that carry a slight positive
charge! These regions of electric charge are
created 7ecause some atoms in the
molecule are often more electronegative
Eelectron(attractingF than others! The
o3ygen atom in a 4ater E?)9F molecule is
more electronegative than the hydrogenatoms& for e3ample& ena7ling the o3ygen
atom to pull electrons a4ay from 7oth
hydrogen atoms! As a result& the o3ygen
atom in the 4ater molecule carries a partialnegative charge& 4hile the hydrogen atoms
carry a partial positive charge! Gater
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
15/22
molecules share a mutual attractionJ
positively charged hydrogen atoms in one
4ater molecule attract negatively charged
o3ygen atoms in near7y 4ater molecules!
Intermolecular attractions affect the rate of
evaporation of a liuid 7ecause strong
intermolecular attractions hold the
molecules in a liuid together more tightly!
As a result& liuids 4ith strong
intermolecular attractions evaporate more
slo4ly than liuids 4ith 4ea1intermolecular attractions! or e3ample&
7ecause 4ater molecules have stronger
mutual attractions than gasoline molecules
Ethe electric charges are more evenlydistri7uted in gasoline moleculesF&
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
16/22
gasoline evaporates more uic1ly than
4ater!
!rocedure
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
17/22
+! Ta1e three china dishes!
)! "ipette out +* ml of each sample!
;! Dish A( Acetone
Dish B( Gater
Dish C( Diethyl ether
:! ecord the 4eights 7efore 7eginning the
e3periment!
an hr and 4ait patiently!
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
18/22
,! ecord the 4eights of the samples
after the given time!
-! Compare the prior and present
o7servations!
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
19/22
!hotograph
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
20/22
"#servation
Amount of each liuid sample ta1enL+*ml
Gater
EgmF
Acetone
EgmF
Dieth
ethe
Egm
Geight of dish
Geight of
Edishsu7stanceF
7efore evaporation
Geight of
Edishsu7stanceF
after evaporation
Geight of su7stanceevaporated
$onclusions
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
21/22
The rate of evaporation of the given threeliuids is in order .(
Diethyl #therNAcetoneNGater
7ecause Gater has e3tensive hydrogen 7onding in 7et4een o3ygen atom of one
molecule and hydrogen atom of another
molecule! But this is a7sent in the case of
Acetone!
8/17/2019 Chemistry Investigatory Project on Evaporation of Liquid
22/22
%%&"'RA!()
https.OOen!4i1ipedia!orgO4i1iO#vaporation
http.OO444!encyclopedia!comOtopicOevapor
ation!asp3
https.OOcommons!4i1imedia!orgO4i1iOCate
gory.MeasuringPinstrumentsPEevaporation
F
https://en.wikipedia.org/wiki/Evaporationhttp://www.encyclopedia.com/topic/evaporation.aspxhttp://www.encyclopedia.com/topic/evaporation.aspxhttps://commons.wikimedia.org/wiki/Category:Measuring_instruments_(evaporation)https://commons.wikimedia.org/wiki/Category:Measuring_instruments_(evaporation)https://commons.wikimedia.org/wiki/Category:Measuring_instruments_(evaporation)http://www.encyclopedia.com/topic/evaporation.aspxhttp://www.encyclopedia.com/topic/evaporation.aspxhttps://commons.wikimedia.org/wiki/Category:Measuring_instruments_(evaporation)https://commons.wikimedia.org/wiki/Category:Measuring_instruments_(evaporation)https://commons.wikimedia.org/wiki/Category:Measuring_instruments_(evaporation)https://en.wikipedia.org/wiki/EvaporationTop Related