WednesdayWednesdayDecember 2, 2009December 2, 2009
(Discussion)(Discussion)
Bell Ringer 12-2-09
Write both the word equation and balanced
formula equation for the following reaction.
Solid zinc (II) sulfide reacts with oxygen gas to produce
solid zinc (II) oxide and gaseous sulfur dioxide.
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AssignmentAssignment PagePage Date Date IssuedIssued
Date Into Date Into GradeSpeedGradeSpeed
Last Day Last Day to Turn Into Turn In
WS: Intermolecular Forces, Hydrogen Bonding, Metals
173 11/16 11/30 12/2
WS: Building Ionic Compounds
177 11/17 12/1 12/8
WS: Building Molecular Compounds
181 11/19 12/3 12/10
WS: Chemical Reactions and Equations
189 12/1 12/8 12/15
Sample ProblemSample ProblemAluminum sulfate and calcium hydroxide are used Aluminum sulfate and calcium hydroxide are used in a water-purification process. When added to in a water-purification process. When added to water, they dissolve and react to produce two water, they dissolve and react to produce two insoluble products, aluminum hydroxide and insoluble products, aluminum hydroxide and
calcium sulfate. These products settle out, taking calcium sulfate. These products settle out, taking suspended solid impurities with them. Write a suspended solid impurities with them. Write a balanced chemical equation for the reaction.balanced chemical equation for the reaction.
AlAl22(SO(SO44))33 + Ca(OH) + Ca(OH)22 → →
Al(OH)Al(OH)33 + CaSO + CaSO44
3
32
Types of Chemical ReactionsTypes of Chemical Reactions
Synthesis ReactionsSynthesis Reactions
Decomposition ReactionsDecomposition Reactions
Single-Replacement ReactionsSingle-Replacement Reactions
Double-Replacement ReactionsDouble-Replacement Reactions
Combustion ReactionsCombustion Reactions
Synthesis ReactionsSynthesis ReactionsIn In synthesis reactionssynthesis reactions (also called (also called
addition reactions), two or more addition reactions), two or more substances combine to form a new substances combine to form a new
compound.compound.
A + X A + X → AX→ AX
2Mg + O2Mg + O22 → 2MgO → 2MgO
2H2H22 + O + O22 → 2H → 2H22OO
16Rb + S16Rb + S88 → 8Rb → 8Rb22SS
CaO + HCaO + H22O → Ca(OH)O → Ca(OH)22
Decomposition ReactionsDecomposition ReactionsIn a In a decomposition reactiondecomposition reaction, a single , a single compound undergoes a reaction that compound undergoes a reaction that
produces two or more simpler produces two or more simpler substances. substances.
AX AX → A + X→ A + X
2H2H22O → 2HO → 2H22 + O + O22
2HgO → 2Hg + O2HgO → 2Hg + O22
2KClO2KClO33 → 2KCl + 3O → 2KCl + 3O22
Single-Replacement ReactionsSingle-Replacement Reactions
In a In a single-replacement reactionsingle-replacement reaction, one , one element replaces a similar element element replaces a similar element
in a compound. in a compound.
A + BX A + BX → AX + B→ AX + B
Mg + 2HCl → MgClMg + 2HCl → MgCl2 2 + + HH22
ClCl22 + 2KBr → 2KCl + Br + 2KBr → 2KCl + Br22
2Al + 3Pb(NO2Al + 3Pb(NO33))22 → 3Pb + 2Al(NO → 3Pb + 2Al(NO33))33
Double-Replacement ReactionsDouble-Replacement Reactions
In a In a double-replacement reactiondouble-replacement reaction, the , the ions of two compounds exchange ions of two compounds exchange
places in an aqueous solution to form places in an aqueous solution to form two new compounds.two new compounds.
AX + BY AX + BY → AY + BX→ AY + BX
HCl + NaOH → NaCl + HHCl + NaOH → NaCl + H22O O
2KI + Pb(NO2KI + Pb(NO33))22 → PbI → PbI22 + 2KNO + 2KNO33
FeS + 2HCl → HFeS + 2HCl → H22S + FeClS + FeCl22
Combustion ReactionsCombustion ReactionsIn a In a combustion reactioncombustion reaction, a carbon-, a carbon-containing substance combines with containing substance combines with
oxygen to produce carbon dioxide and oxygen to produce carbon dioxide and water, and releasing a large amount water, and releasing a large amount
of energy in the form of light and of energy in the form of light and heat.heat.
CX + OCX + O22 → CO→ CO22 + H + H22OO
CHCH44 + 2O + 2O22 → CO → CO22 + 2H + 2H22OO
CC33HH66 + 5O + 5O22 → 3CO → 3CO22 + 4H + 4H22OO
Activity SeriesActivity Series The ability of an element to react is The ability of an element to react is
called the element’s called the element’s activityactivity.. An An activity seriesactivity series is a list of elements is a list of elements
organized according to the ease with organized according to the ease with which the elements undergo certain which the elements undergo certain chemical reactions.chemical reactions.
For For metalsmetals, greater activity means a , greater activity means a greater ease of loss of electrons, to greater ease of loss of electrons, to form positive ions.form positive ions.
For For nonmetalsnonmetals, greater activity , greater activity means a greater ease of gain of means a greater ease of gain of electrons, to form negative ions.electrons, to form negative ions.
Activity SeriesActivity Series The order in which the elements are listed in an The order in which the elements are listed in an
activity series is usually determined by single- activity series is usually determined by single-replacement reactions.replacement reactions.
The most active element, placed at the top in The most active element, placed at the top in the series, can replace each of the elements the series, can replace each of the elements below it from a compound in a single-below it from a compound in a single-replacement reaction.replacement reaction.
An element farther down can replace any An element farther down can replace any element below it but not any above it.element below it but not any above it.
Activity series are used to help predict whether Activity series are used to help predict whether certain chemical reactions will occur.certain chemical reactions will occur.
Activity SeriesActivity Series See Table 8-3.See Table 8-3.
– Ex) According to the Ex) According to the activity series for activity series for metals, aluminum metals, aluminum replaces zinc.replaces zinc. We, therefore, can We, therefore, can
predict that the predict that the following reaction does following reaction does occur:occur:
2Al + 3ZnCl2 2Al + 3ZnCl2 → 3Zn + → 3Zn + 2AlCl2AlCl33
– Ex) Cobalt cannot Ex) Cobalt cannot replace sodiumreplace sodium We, therefore, can We, therefore, can
predict that the predict that the following reaction following reaction does does not not occur:occur:
Co + 2NaCl Co + 2NaCl → no → no reactionreaction
Activity SeriesActivity SeriesSample ProblemSample Problem
Sn + OSn + O22 → SnO → SnO22
Any metal more active than silver will Any metal more active than silver will react with oxygen to form an oxide.react with oxygen to form an oxide.Tin is above silver in the activity Tin is above silver in the activity
series, therefore a reaction will occur.series, therefore a reaction will occur.The product will be tin oxide,The product will be tin oxide,
either SnO or SnOeither SnO or SnO22
Activity SeriesActivity SeriesSample ProblemSample Problem
Cd + Pb(NOCd + Pb(NO33))22 → Pb + Cd(NO → Pb + Cd(NO33))22
An element will replace any element An element will replace any element below it in the activity series from a below it in the activity series from a
compound in aqueous solution.compound in aqueous solution.
Cadmium is above lead, therefore a Cadmium is above lead, therefore a reaction will occur to produce lead reaction will occur to produce lead
and cadmium nitrate.and cadmium nitrate.
Activity SeriesActivity SeriesSample ProblemSample Problem
Cu + HCl → no reactionCu + HCl → no reactionAny metal more active than hydrogen Any metal more active than hydrogen
will replace hydrogen from an acid.will replace hydrogen from an acid.
Copper is not above hydrogen in the Copper is not above hydrogen in the series, therefore no reaction will series, therefore no reaction will
occur.occur.
Activity SeriesActivity SeriesQuestionQuestion
How is the activity series useful in How is the activity series useful in predicting chemical behavior?predicting chemical behavior?
It helps predict whether a It helps predict whether a chemical reaction will occur and chemical reaction will occur and
what the product(s) of the reaction what the product(s) of the reaction will be.will be.
Activity SeriesActivity SeriesQuestionQuestion
Based on the activity series, Based on the activity series, predict whether the following predict whether the following
reaction will occur?reaction will occur?
Ni + HNi + H22O O → →
NoNo
Activity SeriesActivity SeriesQuestionQuestion
Based on the activity series, Based on the activity series, predict whether the following predict whether the following
reaction will occur?reaction will occur?
BrBr22 + KI + KI →→
2KBr + I2KBr + I22
Activity SeriesActivity SeriesQuestionQuestion
Based on the activity series, Based on the activity series, predict whether the following predict whether the following
reaction will occur?reaction will occur?
Au + HCl Au + HCl →→
NoNo
Activity SeriesActivity SeriesQuestionQuestion
Based on the activity series, Based on the activity series, predict whether the following predict whether the following
reaction will occur?reaction will occur?
Cd + HCl Cd + HCl →→
CdClCdCl22 + H + H22
22
Activity SeriesActivity SeriesQuestionQuestion
Based on the activity series, Based on the activity series, predict whether the following predict whether the following
reaction will occur?reaction will occur?
Mg + Co(NOMg + Co(NO33))22 →→
Mg(NOMg(NO33))22 + Co + Co
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Chemical Reactions Chemical Reactions and Equationsand Equations
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