Chemical Reactions

1
Chapter 21

• Chemical Reactions

2
Chemical Reactions

• Def _______________ in which one or more
  substances are converted into _____________
  substances
• _________________ ? Products

yield
3
Conservation of Mass

• Antoine Lavoisier _______s
• Total ____________ of products always equals
  total mass of _________________
• Matter cannot be created or _________________
• Father of _______________ Chemistry

4
Writing Equations

• Chemical Equation ____________________ a
  chemical rxn using formulas and ______________

5
Unit Managers

• Coefficients represent _______________ of units
  of each substance
• 2H2 O2 ? 2H2O

coefficients
6
Writing Equations

• One unit of Nickel(II) chloride, dissolved in
  water, plus two units of sodium hydroxide,
  dissolved in water, produces one unit of solid
  nickel(II) hydroxide plus two units of sodium
  chloride, dissolved in water.
• __________________________________________

7
Chemical Rxns in the Environment

• Iron _________________ Iron(III) Oxide
• Very damaging
• Aluminum reacts with ____ Aluminum Oxide
• Coating, looks __________, protects
• _____________ reacts with air
• Blue-green coating
• ________________

8
Balancing Equations

• Section 2

9
Bicycle Equation

• 4 main parts to __________________
• Frame (F)
• _______________ (W)
• Handlebar (H)
• _______________ (P) Bicycle FW2HP2
• F W H P ? FW2HP2
• F __W H __P ? FW2HP2

10
Balanced Equations

• Balanced Equation has _____________ of atoms
  of each element on both sides of equation
• ___HgO(s) ? ___Hg(l) ___O2(g)
• _______________ atoms on each side
• Write in ___________________
• Reduce if needed

11
Lets Balance!!

• Fe(s) Cl2(g) ? FeCl3(s)
• MgSO4 KNO3 ? Mg(NO3)2 K2SO4
• Li(s) H2O(l) ? LiOH(aq) H2(g)

12
Types of Reactions

• Section 3

13
Types of Reactions

• Organize all rxns into _______ main types
• Combustion
• _____________________
• Decomposition
• Single Displacement
• __________________________

14
Synthesis Rxns

• Def two or more substances ______________ to
  form another
• A B ? ________
• 1 ________________!!
• 2H2(g) O2(g) ? 2H2O(g)

15
Combustion Rxns

• Type of synthesis - _________________
• Def substance reacts with _______________ to
  produce energy in the form of heat and light
• CH4(g) 2O2(g) ? _________(g) 2H2O(g)

16
Decomposition Rxns

• __________________ of Synthesis Rxns
• Def one substance ________________ down into two
  or more substances
• AB ? ___________________
• 1 ___________________!!
• 2H2O2(g) ? 2H2O (g) O2(g)

MnO2
17
Single Displacement

• Def one _____________________ replaces the other
  in a compound
• A BC ? ______________________
• 1 element and 1 _____________________!!
• Cu(s) 2AgNO3(aq) ? Cu(NO3)2(aq) 2Ag(s)

18
Double Displacement

• Def ____________ of one compound replaces the
  ion in another compound
• May form a ______________________ an insoluble
  compound (doesnt dissolve in H2O)
• AB CD ? ____________________
• 2 ___________________ react!!
• Pb(NO3)2(aq) 2NaCl(aq) ? PbCl2(s) 2NaNO3(aq)

19
Chemical Rxns and Energy

• Section 4

20
Energy Exchanges

• All rxns ____________________ or absorb energy
• Energy could be heat, light, ______________, or
  electricity
• In rxns
• bonds breaking _________________ energy
• bonds _________________ releases energy

21
More Energy OUT

• Exergonic rxns ______________ energy
• ______________ energy needed to break bonds than
  released to form bonds
• Light or _____________ is given off
• Exothermic rxn when energy given off is
  primarily ______________
• Feels ____________
• Ex burning wood, dynamite
• Provide most ___________________ to homes and
  industries

22
More Energy In

• Endergonic rxns absorb, ___________, energy
• Require _______________ energy to break bonds
  then to form bonds
• Electricity often _____________ energy to rxns
• Endothermic rxn rxn absorbs __________
• Feels _____________

23
Catalysts and Inhibitors

• Catalyst ______________ up a chemical rxn
• __________________ change rxn, just makes it
  happen faster
• Inhibitors ____________ down chemical rxn
• Preservatives _________, BHA prevent spoilage rxn
• Dont change amount _________________!!! Just
  speed or slow a rxn!!