Properties of Water Lab PDF

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Lab answers for Dr. O'Quinn...

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Pr o pe r t i e so f Wa t e r OBJ ECTI VES:Th eg o a l so f o u re x e r c i s et h i swe e ka r et op r o v i d ey o uwi t has t r o n gc o n c e p t u a l u n d e r s t a n d i n go f t h e r o l eh y d r o g e nb o n d i n gp l a y si np r o d u c i n gt h ef o u rma j o re me r g e n t p r o p e r t i e so f wa t e rd i s c u s s e di ny o u rb o o k . Th e r e f o r e , y o us h o u l db ea b l et od e fi n et h ef o l l o wi n gt e r ms ;c ohe s i on, a dh e s i on, s u r f a c et e ns i on, c a pi l l a r ya c t i on, h y d r ophobi c , h y d r ophi l i c , a mphi pa t hi c , a n dpol a r i t y , a n de x p l a i nt h eme c h a n i s mb ywh i c he a c ho f t h e s et h i n g s wo r k .F o r e x a mp l e , t h ed e fi n i t i o no f c o h e s i o ni st h et e n d e n c yo f l i k emo l e c u l e st os t i c kt oe a c ho t h e r .Th e me c h a n i s mf o r c o h e s i o ni st h a t t h ep o s i t i v ep o l e so f awa t e r mo l e c u l e( i . e . , t h ee d g e swi t ht h eH’ sa t t a c h e d )a r e a t t r a c t e dt ot h en e g a t i v ep o l eo f t h ewa t e r mo l e c u l e( i . e . , t h ee n dwi t ht h ee l e c t r o n e g a t i v eOa t o m) .I f y o ut r u l y u n d e r s t a n dt h e s ec o n c e p t sy o us h o u l db ea b l et oa p p l yy o u ru n d e r s t a n d i n gt o wa r d se x p l a i n i n go b s e r v a b l e p h e n o me n a . Th i sl a bc o n s i s t so f 5p a r t s . Be f or ey oub e gi n, y ou’ l l ne e dt oa s s e mbl et h ef ol l owi ngi t e ms Wa t e r Wa xp a p e r Smo o t h( c l e a n )s u r f a c e , l i k eas ma l l d i s h , o rt h ek i t c h e nc o u n t e r Co i n Oi l ( c o o k i n go i l ) Di s hs o a p F o o dc o l o r i n g _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Pa r t1 : Wa t c ht hi sv i de o: ht t ps : / / www. y out u be . c om/ wa t c h?v = 3 j wAGWk y 9 8 c Q1 . Dr a wt wowa t e r mo l e c u l e st h a t a r e‘ a t t r a c t e d ’ t oo n ea n o t h e ra n de x p l a i nt h e i ra t t r a c t i o n . Wh a t i ss p e c i a l a b o u t t h eh y d r o g e nb o n d s ?Wh a t s i g n i fi c a n c ed o e st h a t h a v et ot h ep r o p e r t i e so f wa t e r ?

Th ep o l a r i t yo f wa t e r mo l e c u l e sr e s u l t si nt h eh y d r o g e na t o msh a v i n gas l i g h t p o s i t i v ec h a r g ea n dt h eo x y g e na t o m h a v i n gas l i g h t n e g a t i v ec h a r g e . Th i ss l i g h t c h a r g e sa t t r a c t t h eh y d r o g e no f o n ewa t e rmo l e c u l et ot h eo x y g e no f a n o t h e rmo l e c u l e , r e s u l t i n gi nah y d r o g e nb o n dt h a t c a nb ee a s i l yb r o k e na n dr e f o r me dq u i c k l y . Th i sg i v e swa t e r i t s p r o p e r t i e so f c o h e s i o na n dh i g hs u r f a c et e n s i o n . Q2 . Wh a t h a p p e n st owa t e rmo l e c u l e swh e nt h e yh e a t u p ?( c i r c l ea l l t h a t a p p l y ) a .Ra n d o mmo t i o n b .Bu mpi n t oo n ea n o t h e r c . Sp e e du p

d .Sl o wd o wn Q3 . Wh a t ’ sh a p p e n i n gd u r i n ge v a p o r a t i o n ? Du r i n ge v a p o r a t i o n , wa t e rmo l e c u l e sa b s o r be n e r g yh e a t a n db e g i nt omo v ev e r yq u i c k l y . On c et h ewa t e r mo l e c u l e s r e a c ht h eh e a t o f v a p o r i z a t i o n , t h e yt r a n s f o r mf r o mal i q u i dp h a s et oag a s e o u sp h a s e . Th emo l e c u l e swi t ht h e h i g h e s t a mo u n t o f e n e r g ye v a p o r a t efi r s t , l o we r i n gt h ea v e r a g ek i n e t i ce n e r g yo f t h eb o d yo f wa t e r s i n c et h e mo l e c u l e st h a t r a i s et h ea v e r a g eh a v ee v a p o r a t e d . Th i sl o we r i n gi na v e r a g ek i n e t i ce n e r g yr e s u l t si nat h eb o d yo f wa t e r c o o l i n g . Q4 . Wh a t p r o p e r t yo f wa t e ri ss t a b i l i z i n gt ol i f e ? Wa t e r ’ sh i g hs p e c i fi ch e a t i ss t a b i l i z i n gt ol i f eb e c a u s ei t a l l o wsf o rwa t e r t oa b s o r bo r r e l e a s ee n e r g yf r o mt h e e n v i r o n me n t wh i l eb a r e l yc h a n g i n gt h ewa t e rt e mp e r a t u r e . Th i sp r o p e r t yh e l p st oc a l ma n dma i n t a i namo d e r a t e c l i ma t et h a t i si n h a b i t a b l ef o ro r g a n i s ms .

Pa r t2 : Pl a ywi t hwa t e r . I t h e l p st oa c t u a l l yp l a ywi t hwa t e rt o o , s on o wy o uwi l l h a v et ofi n ds o meh o u s e h o l d p r o d u c t s ; c o i n , wa t e r ( Ex e r c i s e2 A) ; c o i n , wa t e r , d i s hs o a p( Ex e r c i s e2 B) Ex e r c i s e2 A Ma t e r i a l s : Co i n Wa t e r Q5 . Be f o r ey o uc a r r yo u t t h i se x p e r i me n t , y o u ’ l l wa n t t ofi r s t p r e d i c t wh a t wi l l h a p p e n . So , h o wma n yd r o p so f wa t e r d o y o ut h i n ky o uc a np u t o nt h ec o i nb e f o r ei t r u n so ff ?Ex p l a i ny o u rp r e d i c t i o nb a s e do nwh a t y o uk n o wa b o u t t h e p r o p e r t i e so f wa t e r ? I t h i n kt h ed i mewi l l h o l d2 5d r o p so f wa t e rb e f o r ei t o v e r fl o ws . Th eh y d r o g e nb o n d i n go f wa t e rg i v e si t c o h e s i o na n da v e r yh i g hs u r f a c et e n s i o n , wh i c hwi l l l e a dt ot h ed i meh o l d i n gal o t o f wa t e rb e f o r ei t o v e r fl o ws . Me t hods : 1 . Ge t ac u po f wa t e r , a n dy o u rc o i n 2 . Ma k es u r et h es u r f a c eo f y o u rc o i ni sd r y , t h e nu s i n gt h et i po f y o u r fi n g e r ( o r ad r o p p e r i f y o uh a v eo n ea r o u n d ) , c o u n t h o wma n yd r o p so f wa t e r y o uc a np l a c eo nt h es u r f a c eo f t h ec o i nb e f o r ei t o v e r fl o ws . Dr a wwh a t y o us e ei nt h e s p a c eb e l o ws h o wi n gt h es h a p eo f t h ewa t e ro nt h ec o i na f t e r o n ed r o p , wh e nt h ec o i ni sh a l f f u l l , a n dj u s t b e f o r ei t l o o k sl i k ei t i sg o i n gt oo v e r fl o w.

Ans we rt hef ol l owi ngque s t i ons: Q6 . Ho wma n yt o t a l d r o p sd i dy o ua c t u a l l yg e t o nt h ec o i n ? d I g o t 3 2d r o p so nt h ed i me , a n di t o v e r fl o we da sI p l a c e dt h er 3 3 d r o p .

Q7 . Wh i c hp r o p e r t y( o rp r o p e r t i e s )o f wa t e r i s( a r e ) i l l u s t r a t e di nt h i se x e r c i s e ? Th i se x e r c i s es h o wst h eh i g hs u r f a c et e n s i o no f wa t e rd u et oh y d r o g e nb o n d i n ga n dc o h e s i o n .

Ex e r c i s e2 B Ma t e r i a l s : Co i n Wa t e r Di s hSo a p Q8 . Be f o r ey o uc a r r yo u t t h i se x p e r i me n t , y o u ’ l l wa n t t ofi r s t p r e d i c t wh a t wi l l h a p p e n . Wi l l y o ub ea b l et og e t mo r eo r f e we rd r o p so f wa t e ro n t oy o u r c o i nwi t hal a y e ro f s o a po ni t ss u r f a c e ?Ex p l a i ny o u rp r e d i c t i o nb a s e do nwh a t y o u k n o wa b o u t t h ep r o p e r t i e so f wa t e r ? I t h i n kI wi l l b ea b l et og e t l e s sd r o p so nt h ed i mewi t ht h es o a pb e c a u s ei t wi l l i n t e r f e r ewi t ht h eh y d r o g e nb o n d s b e t we e nwa t e r mo l e c u l e sa n dl o we rt h es u r f a c et e n s i o n . Me t hods : 1 . Wi t hy o u r fi n g e r , s p r e a do n ed r o po f d i s hs o a po v e r t h es u r f a c eo f y o u rd r yc o i n . 2 . Us i n gy o u rfi n g e ra sb e f o r e , a d dd r o p so f wa t e r t ot h ec o i ns u r f a c e .Ke e pac a r e f u l c o u n t o f t h en u mb e ro f d r o p s , a n dd r a wp i c t u r e sa sb e f o r e .

Ans we rt hef ol l owi ngque s t i ons: Q9 . Di dt h ed i s hs o a ph a v ea ne ff e c t o nt h eo u t c o me , i f s oh o w( d e s c r i b ey o u rr e s u l t s ) ? Th es o a pd i dh a v et h eo u t c o meI e x p e c t e d . I n o t i c e di mme d i a t e l yt h ewa t e r s p r e a do u t mu c hq u i c k e r , e v e nwi t ho n l y o n ed r o p . T h es o a pl e dt ot h ewa t e r o v e r fl o wi n ga t d r o p1 6r a t h e rt h a n3 3 . Q1 0 . Wh i c hp r o p e r t y( o rp r o p e r t i e s )o f wa t e ri si l l u s t r a t e di nt h i se x e r c i s e ? Th i sh i g h l i g h t e dt h ei mp o r t a n c eo f wa t e r ’ sc o h e s i o nd u et oh y d r o g e nb o n d i n gt ok e e pah i g hs u r f a c et e n s i o n . Th e s o a pi n t e r f e r e dwi t hh y d r o g e nb o n d i n g , a n dt h es u r f a c et e n s i o nd r o p p e da n di t o v e r fl o we di nh a l f t h et i me .

Pa r t3 : Wa t c ht hi sv i de oa b outwa t e ra ndoi l mi x i ng:( y ou’ l l ha v et oi gnor et h e‘ c ut e ’ a nt hr omo r phi s m! ) ht t ps : / / www. y out u be . c om/ wa t c h?v = h5 y I J XdI t go&v l = e l Q1 1 . Th ev i d e oe x p l a i n swa t e r mo l e c u l e sa sd a n c i n gt o g e t h e r . Sc i e n t i fi c a l l ys p e a k i n g , wh a t i st h i s“ d a n c i n g ” r e f e r r i n g t o ?Wh a t p r o p e r t yo f wa t e ri sd i s p l a y e dh e r e ? Th ed a n c i n gi st h ea t t r a c t i o no f wa t e rmo l e c u l e st oo n ea n o t h e rd u et oh y d r o g e nb o n d s . Th e s eb o n d sa r ev e r yq u i c k , s h o r t l a s t i n g , a n dr a n d o m. Th eh y d r o g e nb o n d sa r ee a s i l yma d ea n db r o k e n , l e a d i n gt oc o h e s i o no f wa t e rmo l e c u l e s . Q1 2 . Wh a t h a p p e n swh e no i l i sa d d e dt owa t e r ?Wh yc a n ’ t o i l mi xwi t hwa t e r ?Ex p l a i nwh a t i t i sa b o u t t h e i rmo l e c u l a r s t r u c t u r et h a t i mp e d e st h e i rmi x i n g . Oi l a n dwa t e r d on o t mi xb e c a u s ewa t e rmo l e c u l e sa r ep o l a rwh e r eo i l mo l e c u l e sa r en o t . Th eo i l mo l e c u l e sa r ea l s o mu c hl a r g e rt h a nwa t e rmo l e c u l e s . Th ewa t e rmo l e c u l e sa n do i l mo l e c u l e ss t i c kt oo n ea n o t h e r , r a t h e rt h a nmi x i n g .

Q1 3 . Wh yc a ns a l t “ d a n c e ”wi t hwa t e rmo l e c u l e s ?Ex p l a i nt h es c i e n c eo f wh a t i sh a p p e n i n gwh e ny o ua d ds a l t t o wa t e r . Th es a l t mo l e c u l e sb r e a ki n t os o d i u ma n dc h l o r i n ei o n s . Th ei o n sh a v ec h a r g e st h a t a l l o wt h e mt ob o n dwi t ht h ep o l a r wa t e r mo l e c u l e s .

Pa r t4 : Cont i nuepl a y i ngwi t hwa t e r . Ex e r c i s e4 A( Wa t e r ) Ma t e r i a l s : Wa t e r Smo o t hs u r f a c e dd i s h , l i k et h eb o t t o mo f ag l a s sc u p , as ma l l p l a t e , o r e v e nt h ec o u n t e r t o p . Wa xPa p e r Q1 4 . Be f o r ey o uc a r r yo u t t h i se x p e r i me n t , y o u ’ l l wa n t t ofi r s t p r e d i c t wh a t wi l l h a p p e n . Pr e d i c t t h es h a p eo f as i n g l e d r o po f wa t e ro nap i e c eo f wa xp a p e ra n do ny o u rs mo o t hs u r f a c e ?Dr a wy o u r p r e d i c t i o n .

Me t hods 1 . Wi t hy o u r fi n g e r , mo v ewa t e ro v e rt ot h es mo o t hs u r f a c ea n dt h ewa xp a p e r . 2 .Ad daf e wd r o p st oe a c hs u r f a c ea n dd r a wwh a t y o us e e . Q1 5 . Dr a wwh a t a c t u a l l yh a p p e n e dt ot h ed r o p so f wa t e ro ne a c hs u r f a c e .

Ans we rt hef ol l owi ngque s t i ons: Q1 6 . Ex p l a i nwh a t h a p p e n e dt ot h ewa t e r d r o p so ne a c hs u r f a c e . Ho wd i dt h e yc o mp a r e ? Th ed r o p so nt h es mo o t hs u r f a c es p r e a do u t ab i t mo r ea n dwe r en o t a sr o u n d e do nt h ee d g e s , wh e r e a st h ed r o p s o nt h ewa xp a p e rs t a y e dv e r yd r o p s h a p e da n dg r e ws l i g h t l yt a l l e ra n dl a r g e rr a t h e rt h a ns p r e a d i n go u t . Q1 7 . Wh i c hp r o p e r t y( o rp r o p e r t i e s )o f wa t e ri si l l u s t r a t e di nt h i se x e r c i s e ? Th i se x e r c i s es h o we dwa t e r ’ sc o h e s i o na n da d h e s i o n . Th ewa t e rd r o p sd on o t a d h e r ewe l l t owa xp a p e rd u et ot h e wa x yc o a t i n g , s oi t s t a y sv e r yd r o p s h a p e da n dd o e sn o t s p r e a do u t . Me a n wh i l e , t h ewa t e rd i da d h e r emo r et ot h e s mo o t hs u r f a c e , l e a d i n gi t t os p r e a do u t mo r e .

Ex e r c i s e4 B Ma t e r i a l s : Oi l ( s o mec o o k i n go i l wi l l wo r k ) Smo o t hs u r f a c e dd i s h , l i k et h eb o t t o mo f ag l a s sc u p , as ma l l p l a t e , o re v e nt h ec o u n t e r t o p . Wa xPa p e r Q1 8 . Be f o r ey o uc a r r yo u t t h i se x p e r i me n t , y o u ’ l l wa n t t ofi r s t p r e d i c t wh a t wi l l h a p p e n . Pr e d i c t t h es h a p eo f as i n g l e d r o po f o i l o nap i e c eo f wa xp a p e r a n do ny o u r s mo o t hs u r f a c e ?Dr a wy o u r p r e d i c t i o n .

Me t hods 1 . Wi t hy o u r fi n g e r , mo v eo i l o v e rt ot h es mo o t hs u r f a c ea n dt h ewa xp a p e r . 2 .Ad daf e wd r o p so f o i l t oe a c hs u r f a c ea n dd r a wwh a t y o us e e .

Ans we rt hef ol l owi ngque s t i ons: Q1 9 . Ex p l a i nwh a t h a p p e n e dt ot h eo i l d r o p sp l a c e do nt h et wos u r f a c e s . Th ed r o p so f o i l o ns mo o t hs u r f a c el a i da l mo s t c o mp l e t e l yfl a t . Th ed r o p so nt h ewa xp a p e rwe r emo r el i k et h ewa t e r o nt h es mo o t hs u r f a c ewh e r et h e ywe r es t i l l r a i s e da n dd r o ps h a p e dr a t h e rt h a nfl a t , b u t n o t s u p e rp r o n o u n c e dl i k e t h ewa t e rd r o p so nt h ewa xp a p e r . Q2 0 . Wh i c hp r o p e r t y( o rp r o p e r t i e s )o f o i l i si l l u s t r a t e di nt h i se x e r c i s e ? Oi l i sn o t p o l a rt h ewa ywa t e r mo l e c u l e sa r e , s oi t h a samu c hl o we rs u r f a c et e n s i o nt h a nwa t e rd o e s . Th i si sb e c a u s e t h emo l e c u l e so f o i l a r en o t a t t r a c t e dt oo n ea n o t h e r a ss t r o n g l ya swa t e rmo l e c u l e sa r et oo n ea n o t h e r .

Pa r t5 : Pl a ywi t hwa t e rabi tmor es i nc ei ti s , a f t e ra l l , t heb a s i sofa l l l i f e ! Ma t e r i a l s : Wa t e r Wa xPa p e r Oi l F o o dc o l o r i n g Q2 1 . Be f o r ey o uc a r r yo u t t h i se x p e r i me n t , y o u ’ l l wa n t t ofi r s t p r e d i c t wh a t wi l l h a p p e n . Pr e d i c t h o wad r o p l e t o f f o o d c o l o r i n gwi l l b e h a v ei nap o o l o f wa t e rd r o p s . Pr e d i c t h o wad r o p l e t o f f o o dc o l o r i n gwi l l b e h a v ei nap o o l o f o i l d r o p l e t s . I b e l i e v et h ef o o dc o l o r i n gwi l l s p r e a dt h r o u g h o u t mo s t o f t h ewa t e rp o o l , b u t n o t i nt h eo i l p o o l . Me t hods : 1 . Pl a c es e v e r a l d r o p l e t so f wa t e r a n ds e v e r a l d r o p l e t so f o i l n e x t t oe a c ho t h e r , b u t f a re n o u g hs e p a r a t e dt op r e v e n t t h e mr u n n i n gi n t oe a c ho t h e r , o nap i e c eo f wa xp a p e ru s i n gt h et i po f y o u rfi n g e r( i . e . , wa s ha n dd r yy o u rh a n d s b e t we e nd r o p p i n gt h ewa t e ra n do i l o nt h ewa xp a p e r ) . 2 .Pe r f o r mt h ee x p e r i me n t b yp l a c i n gad r o po f f o o dc o l o r i n gi n t oe a c ho f y o u rp o o l s . Ans we rt hef ol l owi ngque s t i ons: Q2 2 . Ho wd o e st h ed y eb e h a v ei ne a c hp o o l ? Th ef o o dc o l o r i n gs p r e a do u t t h r o u g ht h ewa t e ra n de v e n t u a l l yc o mp l e t e dc o l o r e dt h ep o o l . Th ef o o dc o l o r i n gs t a y e d wh e r ei t wa sd r o p p e di nt h eo i l p o o l a n dd i dn o t mi x .

Q2 3 : Wh a t d o e st h eb e h a v i o r o f t h ef o o dc o l o r i n gi ne a c hp o o l t e l l y o ua b o u t t h en a t u r eo f t h ef o o dc o l o r i n gs o l u t i o n ?

F o o dc o l o r i n gi smo s t l i k e l ywa t e r b a s e ds i n c ei t d i dn o t c o l o rt h eo i l o r mi xi nwi t ht h eo i l a t a l l , a swa t e ra n do i l d on o t mi xd u et owa t e r ’ sp o l a r i t ya n do i l n o t b e i n gp o l a r ....