Objec&ve:
• Todaywewill…
• Handbackyourtermitelabs&tests.Unit1wrapup.
• Notes:Proper&esofwater
• Lab:WateronaPenny
• CaseStudy:WateronMars
• Sothatwecan…
• Define:Polarity,HydrogenBonding,Cohesion,Adhesion,
HighHeatCapacity&UniversalSolvent
• Explainhowthechemicalstructureofwatergivesitallof
theseproper&es.
• Explainhowtheuniqueproper&esofwatermakelife
possible
BellWork:
•  Silentlyandindividually,pleasecompletethe
ques&onsonthehalfsheet&tled“TermiteLab
Reflec&on.”
•  Pleasedonotturnyourlabsoverun&lIsaytoJ
Thanks, your
labs were
delicious!
Whichfactismostrelevanttoour
termitelab?Why?
A) 
B) 
C) 
D) 
Termitescause1.2billiondollarsofpropertydamageannually.
Termiteseatwood.
Termiteshavedifferentroleswithinthecolony.
Termitesusescent,notvision,tofollowtrails.
D, because you
are trying to
understand why
we follow pen
trails!
ThreeTakeawaysforFutureLabs:
1) Includeonlyrelevantbackground
knowledge.
2) …
3) …
This is NOT quantitative evidence.
“Thetermiteseemedtobea[ractedtotheblueink
fromthebeginning.Whenwesetthetermitefreeto
movearoundthepaper,itimmediatelywentforthe
bluepapermatepen.Buta\erfurtherinves&ga&on,
itstatedtowanderawayfromtheblueinkandwalk
towardstheredbicink.S&llfavoringbluethemost,it
didseemtohaveacertainlikingforthered.”
This is QUANTITATIVE evidence.
“Weplacedthetermiteonthepaperandwhenever
hesteppedonashape,we&medhowlonghewason
itfor.Wefoundthatthetermitestayedonthered
trianglefor5.38seconds,ontheredsquarefor15.84
seconds,andontheredcirclefor3seconds.The
termitewasonthesquarefor428%longerthanthe
circle,soweconcludethatshapedoesaffectthe
termite’sbehavior.”
ThreeTakeawaysforFutureLabs:
1) Includeonlyrelevantbackground
knowledge.
2) MakeyourdataquanDtaDve
(number-based)wheneverpossible.
3) …
WhenarescienDstslikedetecDves?
WhenarescienDstslikelawyers?
DigforALLrelevantdata.
Connectthedots.
–  “Thismeans…”
–  “Thisleadsustoinfer…”
–  “Thishelpsustounderstand…”
ThreeTakeawaysforFutureLabs:
1) Includeonlyrelevantbackground
knowledge.
2) MakeyourdataquanDtaDve
(number-based)wheneverpossible.
3) Argueyourclaimlikealawyer!
Youmayhavediscovered…
I will follow all colors of Bic
and Papermate, because there is
a chemical in the ink that is
similar to the chemicals we
termites use to communicate.
That chemical is not present in
Gel ink, so I will not follow
any color Gel ink.
I also have some difficulty
following sharp corners.
Pleaseturntoyour
Unit1Overviewsheet(1-1):
•  Ifyouwishtodiscussyourresultswithother
students,pleasedosoOUTSIDEofclassDme.
•  Pleasegraphyourresultsandthencompletethe
reflecDonquesDonsontheback.
Unit1WrapUp:
•  PleasecheckthatallofyourUnit1papersarein
chronologicalorder.
•  UseabindercliptoclipallUnit1paperstogether.
(LeavethemINyourbinder.)
•  LeaveyourUnit1OverviewonTOPofyourbinder.
Iwillcomearoundduringlabtodaytocollectit.
Pleasetakeoutyour
“Proper&esofWater”POGIL.
Add “Properties of Water POGIL”
to your Unit 2 Accountability Log.
Polarity
Polarityisthe
uneven
distribu&on
ofchargeina
molecule.
“UniversalSolvent”
Wateriscalledthe“universalsolvent”because
mostsubstanceswilldissolveinwater.
Excep&on:Lipids(oils,fats,waxes,etc)
HydrogenBonds
Theweaka[rac&onsbetweenwatermolecules
arecalledhydrogenbonds.
Cohesion
Cohesionisthea[rac&onbetweenmolecules
oftheSAMEsubstance.
Cohesiononthe
surfaceofa
substanceiscalled
surfacetension!
Adhesion
Adhesionisthe
a[rac&onto
moleculesofa
DIFFERENT
substance.
HighHeatCapacity
WeconsiderwatertohaveaHIGHheat
capacitymeansittakesalotofenergyto
increaseitstemperature.
LowDensityofIce:
H2O is unusual because its solid form
(ice) is LESS dense than its liquid
form (water).
This occurs because the hydrogen
bonds force the molecules into an
organized (and spacious) pattern as
they cool.
PennyLab:
Howmanydropsofwatercanfitonapenny
andWHY?Duebytheendofclass.
Closing:
MILD:Writeasentenceexplainingpolarityin
termsofelectrons.
MEDIUM:Writeasentenceexplaining
hydrogenbondingintermsofpolarity.
SPICY:Writeasentenceexplainingwater’shigh
heatcapacityintermsofhydrogenbonding.
PennyLabConclusionsdueonMonday.
(Pleasetype&print!)
Homework:
Worksheettopreparefortomorrow’squiz.