PowerPoint Lab Answers - Solution Conductivity

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Observations
HC2H3O2(aq):
acetic acid
1
2
3
4
HCl(aq):
5
hydrochloric acid 6
7
NaOH(aq):
8
sodium hydroxide
9
10
CuSO4(aq):
copper(II) sulfate 11
12
Distilled
H 2O
Tap water
NaCl
CuSO4
Sugar
Alcohol
HCl
HCl
HC2H3O2
HC2H3O2
NaOH
NaOH
--5
5
5
5
5
1
5
1
5
1
non
weak
strong
strong
non
non
strong
strong
weak
weak
strong
strong
non
Answers
1. An electrolyte is a compound that, in aqueous
solution, conducts electricity. As liquids: salts,
bases. When aq: salts, acids, bases.
2. HCl(aq):
H+(aq) + Cl –(aq)
NaOH(aq): Na+(aq) + OH–(aq)
CuSO4(aq): Cu2+(aq) + SO42–(aq)
3. Acid: a compound that ionizes in water to form
hydrogen ions. Base: an ionic hydroxide that
dissociates in water to produce hydroxide ions.
4. By placing H in front it indicates that the
compound is an acid (that H comes off as H+).
Answers
5. Dissociation occurs when a (ionic) compound
breaks into its ions in water. Ionization occurs
when a neutral atom or molecule is converted
into an ion (e.g. by water). Ionic compounds
and bases dissociate. Acids ionize.
Dissociation
H
+
H
O
+ Cl + Na
Cl Na + O
H
H
Ionization
+
H
H
HO
+ Cl
Cl H + O
H
H
6. HC2H3O2 is an acid; in solution it is ionized by
H2O, providing ions that conduct electricity.
When it’s pure, there’s no water: it can’t ionize.
7. A strong acid has a greater percentage ionization (most molecules are converted to ions).
8. The % of molecules that form ions in solution.
9. HCl was a strong acid. HC2H3O2 was weak.
10. In the lab, 1 M HCl conducted strongly, 5 M
HC2H3O2 weakly. 1 M HCl had more ions.
11. HCl(aq), HNO3(aq), H2SO4(aq), HBr(aq)
A = anion, M = metal
12. H2SO3: acid, KOH: base, CH3OH: other,
HC3H5O2: acid, Na2C2H3O2:salt, Ba(OH)2: base
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