Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
2/6/2017 1:17 PM
Copyright © 2016 Dan Dill [email protected]
Lecture 18 CH101 A1 (MWF 9 am)
TP Themolarity oftheNaCl aq solutionshownintheimage
isapproximately…
17%
17%
17%
17%
17%
17%
1.
2.
3.
4.
5.
6.
Wednesday, October 19, 2016
• Complete:Dissolvingionicsolids
• Solubilityrules memorizesolubilityguidelinesfig6.28p181
UsedinLab4,QualitativeAnalysis
• Precipitationreactions
• Concentrationsafterprecipitation
20M
20M
2M
0.2M
0.02M
0.02M
Nextlecture: Ionizationofmolecularsolutes;self‐ionizationofwater;
acid‐basereactions:CompetitionforH ;balancingoxidation‐
reductionequations;complexationasLewisacid‐basereaction
Response
Counter
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
10
1
Copyright © 2016 Dan Dill [email protected]
Estimating molarity
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
Ions of salt water allow it to conduct electricity
C6H12O6 aq
Na aq Cl aq
Theconcentrationofwateris55.5mol/L.
Getmolarityfromrelativenumbersofionsandwatermolecules.
10
Copyright © 2016 Dan Dill [email protected]
11
1
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
2/6/2017 1:17 PM
Copyright © 2016 Dan Dill [email protected]
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
TP Themolarity oftheNaCl aqueoussolutionshownintheimage
isapproximately…
Solubilityguidelines
17%
17%
17%
17%
17%
17%
1.
2.
3.
4.
5.
6.
20M
20M
2M
0.2M
0.02M
0.02M
Response
Counter
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
10
13
Copyright © 2016 Dan Dill [email protected]
Soluble ionic compounds, p181 (memorize!)
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
Insoluble ionic compounds, p 181 (memorize!)
22
Copyright © 2016 Dan Dill [email protected]
16
23
2
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
2/6/2017 1:17 PM
Copyright © 2016 Dan Dill [email protected]
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
Precipitation reactions
Precipitation reactions
NaClandAgNO3 arebothsolubleinwater,butAgCl isnot.
IfaqueoussolutionsofNaClandAgNO3,aremixed,theAg aq andCl aq ionscanencounteroneanother.
28
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
29
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
Precipitation reactions
Precipitation reactions
WhenAg aq andCl aq ionsdoencounteroneanother,theywillpairupas
alatticeofAgCl I
Asmorepairsform,theywillaggregate somuchthatsolidAgCl settlesoutof
thesolution.,sothatnoAgCl aq remainsinsolution.
Thisprocessiscalledprecipitation.
30
Copyright © 2016 Dan Dill [email protected]
31
3
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
2/6/2017 1:17 PM
Copyright © 2016 Dan Dill [email protected]
TP Whenaqueoussolutionsofcopper II chlorideandsodiumcarbonate
arecombined,…
25%
25%
25%
25%
1.
2.
3.
4.
noprecipitatewillform
CuCO3 willprecipitate
NaClwillprecipitate
bothCuCO3 andNaClwillprecipitate
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
Quiz Somesolidsodiumcarbonateandsolidpotassiumnitrateare
placedtogetherintopurewater.Afterthoroughstirringandallowing
thingstosettle,…
25% 1. NaNO3 s willhaveprecipitated
25% 2. K2CO3 s willhaveprecipitated
25% 3. NeitherNa2CO3 andnorKNO3 willdissolve,andsowillhavesettled
assolidstothebottomofthesolution
25% 4. Everythingwilldissolve,noprecipitatewillform,andsothesolution
willbeclear
32
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
33
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
A comprehensive example
Concentrationsbeforeandafterprecipitation
Youaregiven150mLofa0.20Maqueoussolutionofammoniumcarbonate
and150mLof0.40Maqueoussolutionofbariumiodide.
NH4 2CO3 s  2NH4 aq CO32 aq
BaI2 s  Ba2 aq 2I aq
37
Copyright © 2016 Dan Dill [email protected]
38
4
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
2/6/2017 1:17 PM
Copyright © 2016 Dan Dill [email protected]
A comprehensive example
Youaregiven150mLofa0.20Maqueoussolutionofammoniumcarbonate
and150mLof0.40Maqueoussolutionofbariumiodide.Thesesolutionsare
mixedandaprecipitateforms.
Writethenet‐ionicequationforthisprocess.
Whatarethespectatorionsforthisprocess?
39
Copyright © 2016 Dan Dill [email protected]
Lecture 18 CH101 A1 (MWF 9 am) Fall 2016
Copyright © 2016 Dan Dill [email protected]
TP Youaregiven150mLofa0.20Maqueoussolutionofammonium
carbonateand150mLof0.40Maqueoussolutionofbariumiodide.These
solutionsaremixedandaprecipitateforms.Thelimitingreagent is….
17%
17%
17%
17%
17%
17%
1.
2.
3.
4.
5.
6.
BaI2 s
NH4 2CO3 s
NH4 aq
Ba2 aq
CO32 aq
I aq
41
5