Chemical Reactions

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Chemical Reactions
2
Chemical Reactions Study Guide

• Chpt. 9.4 Acids and Bases
• Chpt. 11 Balancing, Classifying, and Predicting
  Chemical Reactions
• Chapter 17.1 Thermochemistry (pg. 505-506)
• Chpt. 18.1 Reaction Rates

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Chemistry (2/25)

• Acid/Base Quiz
• Interpreting and Balancing chemical equations
• Due
• Acid/Base Nomenclature worksheet for partial
  credit

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Chemical Reactions Objectives

• 1.Classify and name compounds in chemical
  reactions
• 2.Describe chemical reactions in word and
  chemical equations.
• 3.Balance chemical equations based on the Law of
  Conservation of Mass.
• 4.Identify and classify types of chemical
  reactions and energy changes involved.
• 5.Predict products and energy changes in a
  chemical reaction.
• 6.Identify and test factors that affect the rate
  of chemical reactions.

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Chemistry (2/26)

• Infinite Campus Update
• Acid/Base Nomenclature Worksheet (10pts.)
• Acid/Base Quiz (15pts.)
• Check infinite a lot of missing assignments!
• Objectives
• Interpreting and Balancing chemical equations
• Homework
• Check for missing assignments on infinite campus
• Balancing chemical equations worksheet

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Chemical Reaction Pre-Test

• What is a chemical reaction?
• If matter is conserved during a chemical
  reaction, how is it new matter is created?
• 3. Complete the questions below on the following
  word equation
• Fe(s) O2 (g) ----gt FeO (s)
• Give an example of a reactant from this reaction.
• Give an example of a product from this reaction.
• Balance the chemical equation if needed.
• Circle the type of chemical reaction you think
  this represents.
• synthesis decomposition
  replacement
• neutralization combustion

7
Chemical Reactions

• Substances chemically interact to form different
  substances.
• A substance can be an element or a compound.
• Chemical bonds are broken and created.
• Example Fe(s) O2 (g) ----gt FeO (s)

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Chemical Equations

• Fe O2 ------gt FeO
• Reactants
• Starting substances.
• Chemically interact with one another.
• Usually located to the left of the arrow.
• Products
• Ending substances.
• Substances formed from the chemical reaction.
• Usually located to the right of the arrow.

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Chemical Equations

• Fe(s) O2 (g) ------gt FeO (s)
• Abbreviations for state of matter in an equation.
• (s) substance in solid state
• (g) substance in gaseous state
• (l) substance in liquid state
• (aq) substance dissovled in water.
• (aqueous solution)

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Law of Conservation of Mass

• Fe(s) O2 (g) ------gt FeO (s)
• Are atoms destroyed or created during a chemical
  reaction?
• No, they are just rearranged to produce new
  substances.

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Law of Conservation Of Mass

• Matter is not created or destroyed.
• Matter is just rearranged.
• (mass of reactants mass of products)
• That is why it is important to balance chemical
  equations.

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Law of Conservation of Mass

• Fe(s) O2 (g) ------gt FeO (s)

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Balancing Chemical Equations

• Why? Observe the Law of Conservation of Mass
• Rules
• 1. Add coefficients in front of substances, do
  NOT change subscripts.
• 2. First balance elements that only appear once
  on each side of the equation.
• 3. Make sure coefficients are expressed in lowest
  terms.

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Chemistry (2/27)

• Objectives
• Interpreting and Balancing chemical equations
• Review acid/base quiz
• Homework
• Balancing equations worksheet(due Thursday)
• Law of Conservation of Mass pre-lab qts. and
  hypothesis
• Review acids/bases nomenclature
• Check for missing assignments in infinite campus
• Lab
• Law of Conservation of Mass Lab (Thursday)

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Law of Conservation of Mass Lab

• Homework
• Read through the background and procedures
  section.
• Complete pre-lab questions and hypothesis.

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Balancing Chemical Equations

• a. K MgCl2 ---------gt KCl
  Mg
• b. Ag2O ---------gt Ag O2
• c. CH4 O2 -------gt CO2 H2O

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Chemical Equations
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Chemistry (2/28)

• Objectives
• Interpreting and Balancing Chemical Equations
• Validate the Law of Conservation of Mass with
  scientific evidence.
• Due Today
• Balancing chemical equations worksheet (turn in
  tray)
• Law of Conservation of Mass pre-lab qts. and
  hypothesis
• Homework
• Balancing Chemical Equations practice problems
  (Fri.)
• Check for missing assignments in infinite campus

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Balancing Chemical Equations

• Dihydrogen monoxide sodium (bicarbonate) ---gt
  carbon dioxide sodium hydroxide dihydrogen
  monoxide

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Law of Conservation of Mass Lab

• Purpose
• Validate the Law of Conservation of Mass
• Lab Reminders
• Follow ALL lab procedures carefully.
• Use the same balance for all measurements.

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Acid/Base Nomenclature Quiz
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Chemistry (3/4)

• Infinite Campus Update
• Conservation of Mass Lab (12pts.)
• Balancing Chemical Equations (10pts)
• Objectives
• Balancing Chemical Equation Quiz
• Classifying Chemical Reactions
• Discuss Law of Conservation of Mass Lab
• Homework (Due Wed.)
• Balancing Chemical Equations Worksheet
• Classifying Chemical Reactions Worksheets

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Chemical Reactions Objectives

• Identify and classify types of chemical
  reactions.
• 2. Identify energy changes involved with chemical
  reactions.
• 3. Predict products and energy changes in a
  chemical reaction.

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Chemistry (3/6)

• Infinite Campus Update
• Balancing Chemical Equations Quiz (14pts.)
• Due Today
• Balancing Chemical Equation Worksheet (10pts.)
• Objectives
• Classifying Chemical Reactions
• Identify energy changes associated with chemical
  reactions
• Discuss Balancing Chemical Equation Quiz
• Homework (Due Wed.)
• Classifying Chemical Reactions Worksheets
• Chemical Reaction Lab (pre-lab qts.)

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Chemistry (3/6)

• Infinite Campus Update
• Balancing Chemical Equations Quiz (14pts.)
• Objectives
• Address qts. over Balancing Chemical Equation
  Quiz
• Address qts. over Balancing and Classifying wks
  (homework)
• Discuss Neutralization Reaction
• Introduce Chemical Reaction Lab
• Homework (Due Wed.)
• Chemical Reaction Lab (pre-lab qts.)

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Chemical Reaction Lab

• Purpose To perform and observe eight chemical
  reactions in the lab.
• Homework
• Read the introduction, background, and procedures
  section then answer the pre-lab questions on the
  front. (1-9)

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Balancing Chemical Equation Quiz
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Types of Chemical Reactions

• 1. Synthesis (R S ----gt RS)
• 2. Decomposition (RS------gt R S)
• 3. Single Replacement (T RS ---gt TS R)
• 4. Double Replacement (RS- TU- ---gt RU-
  TS-)
• 5. Combustion (CxHx O2 ----gt CO2
  H2O)
• 6. Neutralization (Acid Base--gt H2O Salt)
• (type of double replacement reaction)

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Synthesis (Combination) Reaction

• 2 or more substances chemically combine to form a
  single substance.
• R S ----gt RS energy
• More energy is released at the end of the
  reaction then is needed to start the reaction.
• (energy released by surroundings gt energy
  absorbed by system)

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Decomposition Reaction

• A compound breaks down into simpler substances.
• RS energy ----gt R S
• More energy is required to start the reaction
  then is released at the end of the reaction.
• (energy absorbed by system gt energy released
  to surroundings)
• .

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Single Replacement Reaction

• An element replaces another element in a
  compound.
• T RS ---gt TS R energy
• Usually energy of surrounding gt energy of system

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Double Replacement Reaction

• Exchange of cations between two ionic compounds.
• RS- TU- ---gt RU- TS- energy
• Usually energy of surrounding gt energy of
  system

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Combustion Reaction

• Fuel (CHO) reacts with oxygen to produce
  predictable substances and energy.
• CxHx(Ox) O2 ----gt CO2 H2O ENERGY
• Always energy of surroundings gt energy of
  system

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Neutralization

• An acid and a base react to produce predictable
  products.
• Changes the pH to 7 (neutral).
• Acid Base -------gt H2O Salt(ionic
  compounds)
• Salt The cation comes from the base and the
  anion from the acid.
• Ex. Na(OH) HCl ? NaCl H2O

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Chemistry (3/11)

• Due
• Classifying and Balancing Chemical Equations
  wksht
• Pre-lab questions(1-9) from Chemical Reaction Lab
• Objectives
• Chemical Reaction Lab
• Homework
• Turn in 3rd qtr. missing assignments for partial
  credit.
• (Deadline Wed. 3/13)

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Chemical Equations to Lab

• Write the reactants for each reaction, and then
  predict what type of reaction you think you are
  going to observe.
• Mg O2 ------gt
• Mg HCl ----gt
• (NH4)2(CO3) -----gt
• Ca(CO3) HCl ----gt
• Zn CuCl2 ----gt
• CuCl2 Na3(PO4) ---gt
• HCl Na(OH) ----gt
• C2H6O O2 -----gt

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Chemical Reaction Lab (3/11)

• Purpose
• Predict the type of reaction for each experiment.
  
• Perform, observe, and record data for each
  chemical reaction.

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Chemistry (3/12)

• Infinite Campus Update
• Classifying and Balancing Chemical Rxtns.
  (10pts.)
• Objective
• Chemical Reaction Lab
• Homework
• Balancing reactions and establishing a conclusion
  for the lab.

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Chemical Reaction Lab (3/12)

• Purpose
• Complete chemical reaction lab.
• Predict products of each reaction.
• Balance each chemical reaction.

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Chemistry (3/13)

• Objectives
• Predict products of each reaction from the lab
• Balance equations(if needed) and establish
  conclusion for lab.
• Homework
• Complete chemical reaction lab

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Chemical Equations to Lab

• Predict the products of each reactant.
• Mg O2 ------gt MgO
• Mg HCl ----gt
• (NH4)2(CO3) -----gt NH3 CO2
  H2O
• Ca(CO3) HCl ----gt CaCl2 H2O
  CO2
• Zn CuCl2 ----gt
• CuCl2 Na3(PO4) ---gt
• HCl Na(OH) ----gt
• C2H6O O2 -----gt

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Chemical Equations to Lab

• Just need to check and see if they are balanced.
• Mg O2 ------gt MgO
• Mg HCl ----gt MgCl H2
• (NH4)2(CO3) -----gt NH3 CO2
  H2O
• Ca(CO3) HCl ----gt CaCl2 H2O
  CO2
• Zn CuCl2 ----gt ZnCl2 Cu
• CuCl2 Na3(PO4) ---gt Cu3(PO4)2 NaCl
• HCl Na(OH) ----gt H2O NaCl
• C2H6O O2 -----gt CO2 H2O

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Conclusion

• A summary that includes the following
• Identify and explain which reactions from the lab
  were synthesis, decomposition, single
  replacement, double replacement, neutralization,
  combustion.
• Based on the data section explain which reactions
  were exothermic and endothermic.
• Which reaction(s) did you like the best and why?
• What did you learn from this lab? (be specific)

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Chemistry (3/14)

• Due Today
• Chemical Reaction Lab
• Objectives
• Classifying reactions
• Predicting products
• Balancing chemical equations
• Homework
• Predicting products and balancing equations wks.

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(Chemistry 3/15)

• Infinite Campus
• Chemical Reaction Lab (26pts. )-3rd qtr.
• Objectives
• Classify reactions
• Predict products
• Balance Chemical Equations
• Homework
• Complete Predicting Products Worksheet.
• Complete internet enrichment problems.
• Monday Quiz over chemical reactions. Study!

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Chemical Reactions

• Predict the products for each reaction and
  balance if needed.
• 3Ca N2 --------gt Ca3N2
  (synthesis)
• b. Cu2S -------gt 2Cu S
  (decomposition)
• 2NaBr F2 ------gt 2NaF Br2 (single
  replace)
• CH4 2O2 -----gt CO2 2H2O
  (combustion)
• e. H2(CO3) 2K(OH) -----gt K2(CO3)
  2H2O (neutralization)

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Chemistry (3/18)

• Objectives
• Classifying, Balancing, Predicting Products
• Activity Series Table and Single Replacement
• Homework
• Activity Series Pre-Lab reading and hypothesis
• Chemical Reaction Quiz (Wednesday)
• Work on study guide (Test Monday)

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Chemical Reactions Bell Ringer

• What are the coefficients that will balance the
  chemical equation below?
• AlCl3 Na(OH) ----gt Al(OH)3 NaCl
• 1,3,1,3
• 3,1,3,1
• 1,1,1,3
• 1,3,3,1
• What type of chemical reaction is expressed
  above?
• Predict the product(s) and balance if needed
• Ba (s) O2 (g) ----------gt

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Predicting Products
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Predicting Products Gallery Walk

• Objective
• Classify Type of Reaction
• Predict Products
• Balance Equation

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Gallery Walk Predicting Products

• At each station complete the following
• Predict the type of reaction
• Predict the products
• Balance the chemical equation if needed

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Chemistry (3/19)

• Objectives
• Activity Series Table and Single Replacement
• Homework
• Activity Series Lab conclusion and post-Lab
  questions
• Chemical Reaction Quiz (Wednesday)
• Work on study guide (Test Monday)

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Activity Series Lab Hypothesis
CuCl2(aq) Ag(NO3) HCl (aq) dH(OH) (l)
Copper (s)
Magnesium (s)
Zinc (s)
Calcium (s)
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Chemistry (3/20)

• Objectives
• Chemical Reaction Quiz
• Discuss Activity Series Lab
• Discuss Endothermic and Exothermic Energy
  Diagrams
• Homework
• Complete Activity Series Lab
• Energy Changes Worksheet
• Work on Study Guide

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Activity Series Lab

• After complete quiz, work on the following
• Activity Series Lab
• Complete conclusion and post-lab questions.

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Chemistry (3/21)

• Infinite Campus Update
• Chemical Reaction Quiz (16pts.)
• Due
• Activity Series Lab
• Objectives
• Interpreting Activity Series Table
• Interpret energy changes in chemical reactions.
• Identify and test factors that affect the rate of
  chemical reactions.
• Homework
• Work on study guide.

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Activity Series Table

• Study Guide Modification omit qts. 18
• Bell Ringer Work on qts. 13 from study guide.

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Thermochemistry

• Study of energy changes during a reaction.
• Energy Review Qts
• When observing a chemical reaction what is the
  difference between the system and its
  surroundings?
• Energy always flows from ____ matter to _____
  matter. (cold, hot)

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Chemistry3/22

• Infinite Campus
• Chemical Reaction Quiz (16pts)
• Assignments Collected
• Activity Series Lab
• Objectives
• Interpret and classify energy changes in
  reactions
• Identify and predict how factors affect the speed
  of a reaction.

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Thermochemistry

• Energy changes that occur within reactions.

Endothermic Reactions
Exothermic Reactions
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Exothermic Reaction

• Energy (H) absorbed lt Energy (H) released.
• The chemical reaction becomes cooler and its
  surroundings gets warmer.
• Test tube gets?
• Energy is on the products side.
• Examples
• combustion of fossil fuels (transportation)
• C8H18 O2 -------gt CO2 H2O energy
• cellular respiration in living organisms
• C6H12O6 O2 ------gt CO2 H2O energy

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Endothermic Reactions

• Energy (H) absorbed gt Energy (H) released
• Chemical reaction gets warmer and its
  surroundings gets cooler.
• Test tube gets ?
• Energy is on the reactants side.
• Ex. Photosynthesis

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Energy Diagram
(H)
(time)
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Chemical Reaction Energy Diagram

• Activation Energy (Ea) The minimum amount of
• energy needed for the reaction to occur.

H Energy change between reactants and
products. ( H H products H reactants)
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Energy Diagram
Does this represent an endothermic or exothermic
reaction?
(H)
(time)
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Energy Diagram
H reactant gt H product Small
activiation energy More energy will be
released in this reaction
(H)
(time)
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Energy Diagram
Does this represent an endothermic or exothermic
reaction?
Activation Energy
(H)
(time)
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Endothermic Energy Diagram

• H reactant lt H product
• Large activation energy
• More energy will be absorbed in this reaction

Activation Energy
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Thermochemistry Examples

• Classify the following examples as endothermic
  (E) or (Ex) exothermic
• If the surroundings gets cooler and the system
  gets warmer.
• Ice cream melting.
• Melted paraffin wax is left at room temperature
  until it solidifies.
• AlCl3 ------gt Al Cl2 energy
• A bright light is created when magnesium reacts
  with oxygen.
• When hydrochloric acid reacts with magnesium the
  test tube will get warm.

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Chemical Reactions Rates

• Reaction Rates how fast the reactants
  chemically change into the products.
• Collision Theory Reactant particles will form
  products when reactants collide
• at the right position.
• and exchange the right amount of kinetic energy.
  

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Rates of Chemical Reactions

• What are factors that can affect the speed of a
  reaction?

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Rates of Chemical Reactions

• What are factors that can affect the rates of
  reactions?
• Temperature
• Concentration of Reactants
• Surface Area of Reactants
• Catalysts
• Inhibitors

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Temperature of Reaction

• What if we increase the temperature of a
  reaction?
• What if we decrease the temperature of a reaction?

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Concentration

• Increase concentration of reactants?
• Decrease concentration of reactants?

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Surface Area

• Increase surface area of reactants?
• Decrease surface area of reactants?

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Catalysts

• Catalysts speed up reactions, but they are not
  apart of the chemical reaction.
• Ex. Enzymes keep your body temperature around
  37oC (98 oF) by speeding up important biological
  reactions.

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Catalyst and Energy Change
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Inhibitors

• Inhibitors slow down a chemical reaction, but are
  not apart of the reaction.
• Inhibitors bind to a catalyst and prevent it from
  speeding up a reaction.
• Ex. Preservation of food. Antioxidants prevent
  foods from becoming stale or moldy.

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Chemical Reactions Study Guide

• Chpt. 9.4 Acids and Bases
• Chpt. 11 Balancing, Classifying, and Predicting
  Chemical Reactions
• Chpt. 18.1 Reaction Rates

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Chemical Reaction Study Guide