Chemical Reactions

Text Reference: 8.2 (pg. 256 - 264)

Types: Synthesis

Example C + O2

OO C + O O C

General: A + B AB

Types: Decomposition

Example: NaCl

General: AB A + B

Cl Na Cl + Na

Types: Single Replacement

Example: Zn + CuCl2

ZnClCl Cu +

General: AB + C AC + B

ClCl Zn Cu+

Types: Double Replacement

Example: MgO + CaS

General: AB + CD AD + CB

SOMg Ca

+O S

Mg Ca+

Types: Combustion

• CHO + O2 CO2 + H2O

• CH4 + O2 CO2 + H2O

• CH3OH + O2 CO2 + H2O

• Reactants: always oxygen with another compound that contains hydrogen and carbon

• Products: always CO2 + H2O

The Activity Series

Text Reference: 8.3 (pg. 265 - 267)

We have looked at several reactions:Fe + CuSO4 Cu + Fe2(SO4)3

Li + H2O LiOH + H2

•The activity series ranks the relative reactivity of metals.•It allows us to predict if certain chemicals will undergo single replacement reactions when mixed.•Metals near the top are most reactive and will replace metals near the bottom.

KNaLiCaMgAlZnFeNiSnPbH

CuHgAgAu

Q: Which of these will react?Fe + CuSO4

Ni + NaCl

Li + ZnCO3

Al + CuCl2

Cu + Fe2(SO4)3

Yes, Fe is above Cu

NR (no reaction)

No, Ni is below Na

Zn + Li2CO3

Cu + AlCl3

Yes, Al is above Cu

KNaLiCaMgAlZnFeNiSnPbH

CuHgAgAu

Yes, Li is above Zn

The reaction with H2O depends on metal reactivity & water temp. Q: will Mg react with H2O?

KNaLiCaMgAlZnFeNiSnPbH

CuHgAgAu

cold H2O

hot H2O

steam

acid

NR

A: No for cold, yes if it is hot/steamMg + H2O

H2 + ZnCl2

Complete these reactions:Al + H2O(steam) Cu + H2O Na + H2O

H2 + Mg(OH)2

H2 + Al(OH)3

H2 + NaOH

Q: Zn + HCl

• All metals will have a specific place in the activity series. For simplicity, only the most common metals are shown.

• The metals near the top of the activity series are more reactive because their valence electrons are more easily removed.

Other Activity Series Information

Mg Cu Zn

Mg + AgNO3

Ag+ Mg(NO3)2

NR

NR

Cu + AgNO3

Ag+ Cu(NO3)2

Zn + AgNO3

Ag+ Zn(NO3)2

AgN

O3

Fe(N

O3 )

3C

uCl2

Mg+ Fe(NO3)3

Fe+ Mg(NO3)2

Zn+ Fe(NO3)3

Fe+ Zn(NO3)2

Mg + CuCl2

Cu + MgCl2

Zn + CuCl2

Cu + ZnCl2

Homework

• P. 264 #1-3

• P. 267 #1-3