Types of Chemical Reactions
Section 8.2
synthesis reaction
combustion reaction
decomposition reaction
single-replacement reaction
double-replacement reaction
precipitate
Section 8.2 Classifying Chemical Reactions
• Classify chemical reactions.
metal: an element that is a solid at room temperature, a good conductor of heat and electricity, and is generally shiny
• Identify the characteristics of different classes of chemical reactions.
Classifying Chemical Reactions
Key Concept 8: There are four types of chemical reactions: synthesis, combustion, decomposition, and replacement reactions.
Types of Chemical Reactions
Types of Chemical Reactions
Type of Reaction:
Synthesis reaction
Explanation: Reaction in which two or more simpler substances (elements) react to produce a single product ( compound).
Types of Chemical Reactions (cont.)
• Other: When two elements react, the reaction is always a synthesis reaction.
General Equation:
A + B AB
Types of Chemical Reactions
Type of Reaction:
Combustion Reaction
Explanation: Reaction where oxygen combines with a substance (normally contains carbon) and releases energy in the form of heat and light.
Types of Chemical Reactions (cont.)
General Equation:
___ + O2 H2O + CO2
CH4 (g) + O2 (g) CO2 (g) + H2O (g)
Types of Chemical Reactions
Type of Reaction:
Decomposition Reaction
Explanation: Reaction in which a single compound breaks down into two or more elements or new compounds.
Decomposition Reactions
• Other: Decomposition reactions often require an energy source, such as heat, light, or electricity, to occur.
General Equation:
AB A + B
Types of Chemical Reactions
Correctly Identify the type of reaction:S = synthesis D = decomposition C = combustion
1. NH3+ H2SO4 (NH4)2SO4
2. C5H9O + O2 CO2 + H2O
3. H2 + O2 H2O
4. NH4OH NH3 + H2O
5. KClO3 (s) KCl (s) + O2 (g)
6. Al (s) + S (s) Al2S3 (s)
7. NaNO3 (s) NaNO2 (s) + O2 (g)
8. CO (g) + O2 (g) CO2 (g)
9. CH4 (g) + O2 (g) CO2 (g) + H2O (g)
10.Mg + N2 Mg3N2
Types of Chemical Reactions
Type of Reaction:
Single Replacement
Explanation: Reaction in which the atoms of one element replace the atoms of another element in a compound.
Replacement Reactions
General Equation:
A + BX AX + B
• Other Info: A metal will not always replace a metal in a compound dissolved in water because of differing reactivates.
• An activity series can be used to predict if reactions will occur.
Hydrogen gas goes here
Types of Chemical Reactions
• Write a balanced chemical equation for each single-replacement reactions involving metals.
• Zn (s) + AgNO3 (aq)
• Zn(s) + H2SO4 (aq)
• Na(s) + H2O(l)
Types of Chemical Reactions
• Write a balanced chemical equation for each single-replacement reactions involving halogens
• Cl2 (g) + HBr(aq)
• I2 + HCl2 (aq)
•Simulations
Types of Chemical Reactions
Type of Reaction:
Double Replacement
Explanation: Reaction in which the ions exchange between two compounds.
Replacement Reactions (cont.)
General Equation:
Replacement Reactions (cont.)
• Other: The solid product produced during a chemical reaction in a solution is called a precipitate.
• All double replacement reactions produce either water, a precipitate, or a gas.
Replacement Reactions (cont.)
• This table shows the steps to write double replacement reactions.
Types of Chemical Reactions
• Write a balanced chemical equation for each double-replacement reactions
BaCl2(aq) + K2CO3 (aq) (a precipitate of barium carbonate is formed)
FeS (s) + HCl (aq) (Hydrogen sulfide gas is formed)
Get out your practice problems.
A. AB. BC. CD. D
Section Assessment
Which of the following is NOT one of the four types of reactions?
A. deconstructive
B. synthesis
C. single replacement
D. double replacement
A. AB. BC. CD. D
Section Assessment
The following equation is what type of reaction?
KCN(aq) + HBr(aq) → KBr(aq) + HCN(g)
A. deconstructive
B. synthesis
C. single replacement
D. double replacement
Solution
Everyday definition• Answer to a problem• A type of liquid
Chemistry• Key Concept 14:
Solution- uniform mixture that can contain solid, liquid, or gases
Solution = Homogenous mixtureThey are synonyms
How a solution is made?
• Solution consist of a solvent and solute.
• Key Concept 15: Solvent- the substance that dissolves the solute to form a solution; most plentiful substance in the solution.
• Key Concept 16: Solute- one or more substance dissolved in a solution.
• Dissociation
• Solubility is physical properties.– Physical properties are those properties that can be
observed or measured without affecting the composition of the sample.
• Key Concept 17: Solubility is the maximum quantity of a substance that may be dissolved in another. The maximum amount of solute that may be dissolved in a solvent.
Solubility
Effect of Temperature on Solubility
Solubility• depends on temperature• of most solids increases as temperature
increases• of gases decreases as temperature
increases• What is sodium chlorides solubility?
– Water: 359 g/L– Ammonia: 21.5 g/L– Methanol: 14.9 g/L
White Solid
Water + universal indicator
Water (at room
temperature)HCl Methanol Iodine
Temp of solubility in
water
Baking Soda
GreenSlightly soluble
Produces gas
Insoluble ---------- 50 C
SugarYellow-orange
Soluble ---------- InsolubleTurns blue
20 C
Benzoic Acid
Pink Insoluble ---------- Soluble ---------- 100 C
Flour Orange Insoluble ---------- InsolubleTurns blue
insoluble
Sodium Chloride
Orange soluble ----------Slightly soluble
---------- 20 C
•30
Soluble and Insoluble Salts
Key Concept 18: Ionic compounds that
• dissolve in water are soluble salts
• do not dissolve in water are insoluble salts
•31
Equations for Forming Solids
A full equation shows the formulas of the compounds.Pb(NO3) 2(aq) + 2NaCl(aq) PbCl2(s) + 2NaNO3(aq)
An ionic equation shows the ions of the compounds.Pb2+(aq) + 2NO3
−(aq) + 2Na+(aq) + 2Cl−(aq)
PbCl2(s) + 2Na+(aq) + 2NO3−(aq)
Key Concept 19: A net ionic equation shows only the ions that form a solid.
Pb2+(aq) + 2Cl−(aq) PbCl2(s)
Quick Demo: DR Visual
Lead (II) Nitrate Sodium ChloridePb(NO3) 2 2NaCl
1. How do I make an solution?2. What is the solvent and the solute?3. What happens during dissociation?4. What happens in a double replacement reaction?
Pb(NO3) 2 (aq) + 2NaCl(aq) PbCl2(s) + 2NaNO3(aq)
Part 1:(2.5 pts) Purpose: To determine whether or not a reaction occurs and to predict the products of a reaction.
Title: Determining Solubility to Solve Double Replacement Reaction (70 pts)
(7.5 pts) Safety:• We are working with acids; gloves, goggles, and aprons must
be worn properly at all times.• All chemicals must be disposed of in specified waste beakers
in the fume hoods. These chemicals are toxic and will harm the environment if not disposed of properly.
• Do not eat, drink, or apply the chemicals to skin. Many of these chemicals are highly corrosive and in addition to being toxic, they will burn your skin and muscle tissue. Ouch!
• If any of the chemicals get on your skin/eyes you MUST wash exposed area for 15 minutes in eye wash/shower.
Title: Determining Solubility to Solve Double Replacement Reaction
(10 pts) Data Table and Results
Title: Determining Solubility to Solve Double Replacement Reaction
Beginning
Nitrate
HCl
added
H2SO4
added
NaOH
added
LiNO3
KNO3
Mg(NO3)2
Ca(NO3)2
Co(NO3)2
Cu(NO3)2
AgNO3
Pb(NO3)2
(10 pts) Part 2-1. All nitrate salts are __________.2. Most salts containing ______ and ________ cations are
soluble. 3. All cations from ______________ are soluble. In addition NH4
+1 salts are soluble.
4. Salts with halogen anions are usually _____________.5. Most sulfate salts are __________. Exceptions include the
cations __________ and ____________. 6. Hydroxides are usually ___________ except those containing
cations from __________.
Title: Determining Solubility to Solve Double Replacement Reaction
(20 pts) Part 3-1.-11. that you will need to answer in your lab notebook by predicting products of the double replacement reaction.
( 20) Part 4-Correctly using solubility tables and charts
Title: Determining Solubility to Solve Double Replacement Reaction