An contains one or more dissolved substances called in water The is the most plentiful substance in a solution Water is always the solvent in an aqueous solution ID: 807512
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Slide1
__________________________An __________________ contains one or more dissolved substances (called __________) in water. The ____________is the most plentiful substance in a solution.Water is always the solvent in an aqueous solution. Both molecular and ionic compounds can dissolve in water.
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Ch 9 Section
3: Reaction in Aqueous Solutions
1
Slide2Molecular Compounds in SolutionSome solutes remain as molecular compounds when dissolved in water.Ex: __________________Molecular compounds must be polar to dissolve in water. Nonpolar molecular substances will not dissolve in water.Other molecular compounds form ions when dissolved in water to form acids.HCl (hydrogen chloride) gas, for example, forms hydrogen ions and chloride ions when dissolved in water.HCl(aq) is called hydrochloric acid
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Slide3Ionic Compounds in SolutionIonic compounds consist of a cation and anionWhen ionic compounds dissolve in water their ions separation in a process called dissociation.Types of Reactions in Aqueous Solutions 1. Reactions that form precipitates Ex: Aqueous solutions of sodium hydroxide and copper(II) chloride react to form the precipitate copper(II) hydroxide.
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3
Slide4The chemical equation for the formation of a precipitate does not show the details.Ionic equations show the details for the molecular equation 2NaOH(aq) + CuCl2(aq) → 2NaCl(aq) + Cu(OH)2(s)Complete ionic equation shows all the particles in solution.Net ionic equation show only the particles participating in the reaction.
Spectator ions that are not part of the reaction are left out.
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4
Slide5Copyright © McGraw-Hill Education5 2. Reactions that form water
Slide6Copyright © McGraw-Hill Education6 3. Reactions that form Gas
Slide7Reactions in Aqueous SolutionsCopyright © McGraw-Hill Education
Reactions That Form a Precipitate
Use with Example Problem 3.
Problem
Write the chemical, complete ionic
, and
net ionic equations for the reaction
between
aqueous solutions of barium
nitrate and
sodium carbonate that forms the precipitate barium carbonate.
Response
ANALYZE THE PROBLEM
You are given the word equation for the reaction between barium nitrate and
sodium carbonate
. You must determine the chemical formulas and relative amounts of all
reactants and
products to write the balanced chemical equation. To write the complete ionic equation
, you
need to show the ionic states of the reactants and products. By crossing out
the spectator
ions from the complete ionic equation, you can write the net ionic equation
. The
net ionic equation will include fewer substances than the other equations.
SOLVE FOR THE UNKNOWN
Write the correct chemical formulas and physical states for all substances involved
in the
reaction.Ba(NO3)2(aq) + Na2CO3(aq) → BaCO3(s) + NaNO3(aq)Balance the skeleton equation.Ba(NO3)2(aq) + Na2CO3(aq) → BaCO3(s) + 2NaNO3(aq)Show the ions of the reactants and the products.Ba2+(aq) + 2NO3−(aq) + 2Na+(aq) + CO32−(aq) → BaCO3(s) + 2Na+(aq) + 2NO3−(aq)
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Slide8Reactions in Aqueous SolutionsCopyright © McGraw-Hill Education
Reactions That Form a Precipitate
EVALUATE THE ANSWER
The net ionic equation includes fewer substances than the other equations because it
shows only
the reacting particles. The particles composing the solid precipitate that is the result
of the
reaction are no longer ions.
SOLVE FOR THE UNKNOWN
Cross out the spectator ions from the complete ionic equation.
Ba
2+
(aq) +
2NO
3
−
(aq)
+
2Na
+
(aq)
+ CO
3
2−
(aq) → BaCO
3
(s) + 2Na+(aq) + 2NO
3−(aq)Write the net ionic equation.Ba2+(aq) + CO32− → BaCO3(s)8
Slide9Types of Reactions in Aqueous SolutionsGases that are commonly produced are carbon dioxide, hydrogen cyanide, and hydrogen sulfide. 2HI(aq) + Li2S(aq) → H2S(g) + 2LiI(aq)Another example is mixing vinegar and baking soda, which produces carbon dioxide gas. HCl(aq) + NaHCO3(aq
) → H2CO3(aq) + NaCl
(aq)H2CO3(aq) decomposes immediately
. H2CO
3
(
aq
) → H
2
O(l) + CO
2
(g)
Reactions in Aqueous Solutions
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9
Slide10Reactions in Aqueous SolutionsCopyright © McGraw-Hill Education
Reactions that Form Water
Use with Example Problem 4.
Problem
Write the chemical,
complete ionic
, and net ionic equations for the reaction
between hydrochloric acid
and aqueous lithium
hydroxide
. This reaction produces
water and
aqueous lithium chloride.
Response
ANALYZE THE PROBLEM
You are given the word equation for the reaction that occurs
between hydrochloric
acid and aqueous lithium hydroxide to produce water
and aqueous
lithium chloride. You must determine the chemical formulas
for and
relative amounts of all reactants and products to write the
balanced chemical
equation. To write the complete ionic equation, you need
to show
the ionic states of the reactants and products. By crossing out
the spectator
ions from the complete ionic equation, you can write the netionic equation.SOLVE FOR THE UNKNOWNWrite the skeleton equation for the reaction and balance it.HCl(aq) + LiOH(aq) → H2O(l) + LiCl(aq)Show the ions of the reactants and the products.
Cross
out the spectator
ions from
the complete
ionic equation.
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Slide11Reactions in Aqueous SolutionsCopyright © McGraw-Hill Education
Reactions that Form Water
EVALUATE THE ANSWER
The net ionic equation includes fewer substances than the
other equations
because it shows only those particles involved in the
reaction that
produces water. The particles that compose the product water
are no
longer ions.
SOLVE FOR THE UNKNOWN
Write the net
ionic equation.
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Slide12Reactions in Aqueous SolutionsCopyright © McGraw-Hill Education
Reactions that Form Gases
Use with Example Problem 5.
Problem
Write the chemical,
complete ionic
, and net ionic equations for the reaction between
hydrochloric acid
and aqueous sodium sulfide, which produces h
ydrogen sulfide gas
.
Response
ANALYZE THE PROBLEM
You are given the word equation for the reaction between
hydrochloric acid
(
HCl
) and sodium sulfide (
Na
2
S
). You must write the
skeleton equation
and balance it. To write the complete ionic equation,
you need
to show the ionic states of the reactants and products. By
crossing out
the spectator ions in the complete ionic equation, you can write the net ionic equation.SOLVE FOR THE UNKNOWNWrite the correct skeleton equation for the reaction.HCl(aq) + Na2S(aq) → H2S(g) + NaCl(aq)Balance the skeleton equation.2HCl(aq) + Na2S(aq) → H2S(g) + 2NaCl(aq)Show the ions of the reactants and the products.2H+(aq) + 2Cl
−
(
aq) +
2Na
+
(
aq) +
S
2−
(
aq)
→ H
2
S(g
) +
2Na
+
(
aq) + 2Cl−(aq)Cross out the spectator ions from the complete ionic equation.2H+(aq) + 2Cl−(aq) + 2Na+(aq) + S2−(aq) → H2S(g) + 2Na+(aq) + 2Cl−(aq)12
Slide13Reactions in Aqueous SolutionsCopyright © McGraw-Hill Education
Reactions that Form Gases
EVALUATE THE ANSWER
The net ionic equation includes fewer substances than the
other equations
because it shows only those particles involved in
the reaction
that produce hydrogen sulfide. The particles that
compose the
product are no longer ions.
SOLVE FOR THE UNKNOWN
Write the net ionic equation in its smallest whole-number ratio.
2H
+
(
aq) +
S
2-
(
aq) →
H
2
S(g)
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Slide14Types of Reactions in Aqueous SolutionsTwo reactions can be combined and represented by a single chemical reaction.Reactions in Aqueous Solutions
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14
Slide15Types of Reactions in Aqueous SolutionsReaction 1 HCl(aq) + NaHCO3(aq) → H2CO3(aq) + NaCl(aq)Reaction 2 H2CO3(aq) → H2
O(l) + CO2(g)Combined equationHCl
(aq) + NaHCO3(aq) + H2CO3(
aq) → H2CO3(
aq
) +
NaCl
(
aq
) + H
2
O(l) + CO
2
(g)
Overall equation
HCl
(
aq
) + NaHCO
3
(
aq
) → H
2
O(l) + CO
2(g) + NaCl(aq)Reactions in Aqueous Solutions
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Slide16Reactions in Aqueous SolutionsCopyright © McGraw-Hill EducationReviewEssential QuestionsWhat are aqueous solutions?How are complete ionic and net ionic equations written for chemical reactions in aqueous solutions?
How can you predict whether reactions in aqueous solutions will produce a precipitate, water, or a gas?Vocabulary
aqueous solutionsolute
spectator ion
net ionic equation
solvent
complete ionic
equation
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