Reaction Types Chemistry Dr. May

Single Displacement Reaction A Compound and an element form a compound and an element A Compound and an element form a compound and an element C + AB  CB + A C + AB  CB + A Zn + 2 HCl  ZnCl 2 + H 2  Zn + 2 HCl  ZnCl 2 + H 2 

May I Have This Dance ? Dancer C steps in to dance with B replacing A Dancer C steps in to dance with B replacing A C + AB  CB + A C + AB  CB + A

Single Displacement Reactions Zn + 2 HCl  Zn + 2 HCl  2 Al + 6 HCl  2 Al + 6 HCl  Mg + 2 HNO 3  Mg + 2 HNO 3  Zn + H 2 SO 4  Zn + H 2 SO 4  ZnCl 2 + H 2  2 AlCl H 2  Mg(NO 3 ) 2 + H 2  ZnSO 4 + H 2 

Single Displacement Reactions Cu + 2 AgNO 3  Cu + 2 AgNO 3  2 Fe + 2 CuSO 4  2 Fe + 2 CuSO 4  3 Al + 2 CuCl 2  3 Al + 2 CuCl 2  Mg + CuSO 4  Mg + CuSO 4  Cu(NO 3 ) Ag Fe 2 (SO 4 ) Cu 3 AlCl Cu MgSO 4 + Cu

Activity Series Li, K, Ca, Na, Mg, Al, Zn, Cr, Fe,Ni, Sn, Pb H Cu, Hg, Ag, Pt, Au Will React With Acid Will Not React With Acid Acid Most Active Least Active HCl + Zn  ZnCl 2 + H 2 

Driving Force A single displacement reaction is driven by the electron affinity of the elements 2 AgNO 3 + Cu  Cu(NO 3 ) Ag 2 Ag NO 3  1 + Cu 0  Cu NO 3  Ag 0 Silver wants electrons more than copper 2 Ag +1 + Cu 0  Cu Ag 0 Copper is oxidized and silver is reduced

Double Displacement Reaction Two compounds form two different compounds Two compounds form two different compounds AB + CD  AD + CB AB + CD  AD + CB HCl + KOH  KCl + HOH HCl + KOH  KCl + HOH

Let’s Trade Partners Dancer A takes D and dancer C takes B Dancer A takes D and dancer C takes B AB + CD  B + D  AB + CD  B + D  C A CB + AD

Double Displacement Reactions HCl + NaOH  HCl + NaOH  2 HCl + Ca(OH) 2  2 HCl + Ca(OH) 2  2 KI + Pb(NO 3 ) 2  2 KI + Pb(NO 3 ) 2  NH 4 Cl + KOH  NH 4 Cl + KOH  NaCl + HOH CaCl HOH PbI 2  + 2 KNO 3 KCl + NH 4 OH

Driving Double Displacement Formation of a precipitate (AgCl  ) Formation of a precipitate (AgCl  ) Formation of a non-ionized material (H 2 O) Formation of a non-ionized material (H 2 O) Formation of a gas (CO 2  ) Formation of a gas (CO 2  )

Formation of a precipitate AgNO 3 + KCl  AgCl  + KNO 3 Silver chloride precipitates from solution and drives the reaction to the right

Formation of a non-ionized material HNO 3 + KOH  HOH + KNO 3 Water is covalently bonded and does not ionize, driving the reaction to the right.

Formation Of A Gas 2 HNO 3 + K 2 CO 3  2 KNO 3 + H 2 CO 3 HOH + CO 2  Carbonic Acid is unstable and decomposes to form water and carbon dioxide, driving the reaction to the right 

No Reaction If there is no driving force, If there is no driving force, Then there is no reaction Then there is no reaction NaCl + KNO 3  No Reaction Na +1 + Cl  1 + K +1 + NO 3  1  Na +1 + Cl  1 + K +1 + NO 3  1

Synthesis Reaction Two or more materials combine to form a new compound Two or more materials combine to form a new compound A + B  AB A + B  AB 2 H 2 + O 2  2 H 2 O 2 H 2 + O 2  2 H 2 O

Materials Combine Two or more materials combine to form a new compound Two or more materials combine to form a new compound 2 H 2 + O 2  2 H 2 O 2 H 2 + O 2  2 H 2 O Hydrogen is oxidized (Loses electrons) Oxygen is reduced (Gains electrons)

Synthesis Reactions Na + Cl 2  Na + Cl 2  N H 2  N H 2  4 Na + O 2  4 Na + O 2  4 Fe + 3 O 2  4 Fe + 3 O 2  2 NaCl 2 NH 3  2 Na 2 O 2 Fe 2 O 3  Oxidized  Reduced  New Compound

Decomposition Reactions A compound breaks apart to form two or more new materials A compound breaks apart to form two or more new materials AB  A + B AB  A + B 2 KClO 3  2 KCl + 3 O 2 2 KClO 3  2 KCl + 3 O 2

Compounds Break Apart A compound breaks apart to form two or more new materials A compound breaks apart to form two or more new materials 2 KClO 3  2 KCl + 3 O 2 2 KClO 3  2 KCl + 3 O 2

Decomposition Reactions H 2 CO 3  H 2 CO 3  NH 4 OH  NH 4 OH  H 2 O  H 2 O  CaCO 3  CaCO 3  H 2 SO 4  H 2 SO 4  H 2 O + CO 2  H 2 O + NH 3  H 2  + O 2  CaO + CO 2  H 2 O + SO 3 

Combustion Reactions A hydrocarbon compound combines with oxygen to form CO 2 plus H 2 O A hydrocarbon compound combines with oxygen to form CO 2 plus H 2 O C x H y + O 2  CO 2 + H 2 O C x H y + O 2  CO 2 + H 2 O C 3 H O 2  3 CO H 2 O C 3 H O 2  3 CO H 2 O

Green House Gas C 7 H O 2  7 CO H 2 O C 7 H O 2  7 CO H 2 O Burning gasoline gives CO 2 and H 2 O

Combustion Reactions CH O 2  CH O 2  2 C 2 H O 2  2 C 2 H O 2  C 3 H O 2  C 3 H O 2  2 C 4 H O 2  2 C 4 H O 2  C 5 H O 2  C 5 H O 2  CO H 2 O 4 CO H 2 O 3 CO H 2 O 8 CO H 2 O 5 CO H 2 O Natural Gas Propane Butane Jet Fuel

Hydrocarbon Vs. Hydrogen Fuel 2 H 2 + O 2  2 H 2 O C 5 H O 2  5 CO H 2 O  Water is the only product  Forms lots of greenhouse gas

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