do-now: “17.4 hess’s law notes write down today’s flt … · take out your calculator,...

Chemistry Monday, May 7th – Tuesday, May 8th, 2018

Do-Now: “Ch. 10/16 Test Day Do-Now” 1. Write down today’s FLT 2. Tell me two differences between

“endothermic” and “exothermic” reactions/values.

3. What are our three types of heat transfer?

4. What are indicators? 5. Use a pro-talk sentence frame to tell me

about ΔG. 6. Take out your ToC and planner J

Test • Youmayhaveoutyourstampedvocabularychartand/orunitreviewpacket

• Noiselevel0• Eyesonyourownpaper• Checkyouranswers• Flipoverwhendone

CW • Vocabchart

Chemistry Wednesday, May 9th – Thursday, May 10th,

2018

Do-Now: “Video Notes: Kinetics” 1.  Write down today’s FLT 2.  How did you feel about our last unit test? 3.  How does ΔH differ between exothermic and

endothermic reactions? 4.  What does it mean if ΔG < 0? 5.  What does “molarity” refer to? 6.  Bob is performing a chemical reaction in a

lab, but his reaction is going very slowly. What do you think Bob could do to speed up the reaction? Make an educated guess if necessary.

7.  Take out your ToC and planner J

Video Notes •  Before we start our new notes, we will

watch a video overviewing the concept of chemical kinetics

•  During the video, write down five facts that you learn about kinetics

•  Focus on new information

FLT •  I will be able to identify four factors that

influence the rate of a chemical reaction by completing Ch. 17 Notes Part A

Standard HS-PS1-5:Applyscientificprinciplesandevidencetoprovideanexplanationabouttheeffectsofchangingthetemperatureorconcentrationofthereactingparticlesontherateatwhichareactionoccurs

Ch. 17 A: Rates of Reaction

Recall

Recall •  Thermodynamics: •  The study of energy changes that

accompany chemical and physical processes

Recall •  If we are discussing thermodynamically

favorability, what should we be considering? •  Do any of these factors give us information

about the rate of a reaction?

Doallreactionsoccuratthesamerate?

ReactionRates•  ChemicalKinetics=Thestudyofthespeedwithwhichreactantsareconvertedtoproducts

ReactionRates•  ReactionRate=Thechangeinconc’ofareactantorproductperunitoftime

Aretherefactorsthataffecttherateofthereaction?

Collision Theory

Collision Theory •  When suitable particles of the reactant hit each

other, only a certain % of the collisions cause any noticeable or significant chemical change

Collision Theory •  Collision Theory (to successfully create

products): ① Molecules must collide with sufficient

activation energy ② Molecules must collide in the correct

orientation •  Only successful collisions will lead to chemical

changes (breaking preexisting bonds and forming all new bonds)

•  This results in the products of the reaction

Collision Theory

Collision Theory

Energy Diagrams

Energy Diagrams •  Recall: we can diagram a reaction’s energy vs.

progress

Energy Diagrams •  Activation Energy (Ea) = the minimum E

required for molecules to react •  Ea is the difference in energy from the reactants

to the peak of the energy diagram

Energy Diagrams •  The greater the Ea, the slower the reaction.

Energy Diagrams •  The peak represents a high energy transition

state (called the activated complex ). Bonds are breaking/forming before the final products are made.

Collision Theory

Factors That Affect Rxn Rate

28

Factors That Affect Rxn Rate 1. Temperature 2. Surface Area 3. Concentration 4. Presence of a Catalyst

Factors That Affect Rxn Rate 1.  Temperature •  Higher T = Higher rxn rate •  Increasing the T increases the avg. KE of

molecules. •  Faster molecules = more collisions •  Higher E collisions = more successful collisions

Factors That Affect Rxn Rate •  This means it’s more likely that bonds will be

broken and new bonds will form. •  An increase in T produces more successful

collisions that are able to overcome the needed activation energy, therefore, a general increase in rxn rate with increasing T

Factors That Affect Rxn Rate 2. Surface Area •  Greater SA = Greater rxn rate •  The amount of “exposed surface” will directly

affect speed

Surface Area of Reactants

Factors That Affect Rxn Rate 3. Concentration •  Higher Conc’ of reactants = Higher rxn rate

(usually) •  The more molecules present, the more collisions

occur, the faster the reaction proceeds, the greater the rate.

Factors That Affect Rxn Rate 4. Presence of a Catalyst •  Catalysts = substances that speed up rxns •  Catalysts are not consumed in chemical rxns,

and can be reused

Factors That Affect Rxn Rate •  Most catalysts work by lowering the Ea

needed for the rxn to proceed – therefore, collisions are more successful and the rate increases

•  We can see this in a rxn pathway

37

38

39

Pair-Share-Respond 1.  Definetheterm“reactionrate”2.  Whatarefourfactorsthataffectrxn

rate?3.  Explainhowtemperatureaffectsthe

reactionrate.Bespecific.4.  Notallreactantsformproducts.What

doescollisiontheorytellusaboutwhichreactantsareabletoformproducts?

5.  Defineactivationenergyandhowcatalystscanaffectit.

Chemistry Friday, May 11th – Monday, May 14th, 2018

Do-Now: “Video Notes: Equilibrium” 1.  Writedowntoday’sFLT.2.  Whatarefourfactorsthatcanaffectthereaction

rate?3.  Twomoleculescollidewithsufficientactivation

energy;however,theydonotformproducts.Whymightthisbe?

4.  DrawanenergydiagramforanENDOTHERMICreaction.LabeltheΔH,reactants,products,activationenergy,andtransitionstate.

5.  Addalineinadifferentcolortorepresenttheeffectonyourenergydiagramwhenacatalystisadded.

6.  TakeoutyourToCandplannerJ

Video Notes •  We will now watch a video overviewing

the concept of chemical equilibrium •  During the video, write down five facts that

you learn about equilibrium •  Focus on:

– What is equilibrium? – What is reversibility? – What does this look like graphically? – Do reactions “end”, and how do you know?

FLT •  I will be able to model the concept of

chemical equilibrium by completing Dueling Cylinders Mini-Lab

Standard HS-PS1-6:Refinethedesignofachemicalsystembyspecifyingachangeinconditionsthatwouldproduceincreasedamountsofproductsatequilibrium

Dueling Cylinders •  We will complete a mini-lab to investigate

the concept of equilibrium

What’s in a line graph?

DataTable1Time (independent)

Number of people in hallway (dependent)

0 min 32 2 min 29 4 min 17 6 min 3

Graph 1

The effect of _________on__________

Skill2—Interpretlinegraphsandcreatea

claim

With the person sitting next to you, make a claim based on the data displayed in graph. Your claim must be based on evidence.