warm - up

Update your Table of Contents Write your homework – leave it to be stamped

Get your homework out to be checked! On your whiteboard, please draw a T-Chart compare and contrast endothermic & exothermic reactions with your table partner

WARM - UP

Date Session#

Activity Page#

10/16 -10/17

19 Rate of Reaction Note/Lab Guide 31

Chemistry Vocabulary List 32

The last few classes we focused on the idea of “What Goes In, Must Come Out,” BUT the Law of Conservation of Mass does not tell us anything about why a reaction occurs in the first place or the

rate/speed at which they occur…

Review…

6CO2 + 6H2O + energy --> 6O2 + C6H12O6

◦What is this the chemical equation for?◦Photosynthesis

6O2 + C6H12O6 --> 6H2O + 6CO2 + energy

◦What is this the chemical equation for?◦Cellular Respiration

Endothermic or Exothermic?

The Rate of Reaction (speed) is dependent on the number of collisions between the molecules. What variables would increase/decrease the number of successful collisions?

With your group, brainstorm a list of things that you think affect the rate, or speed, of a chemical reaction and write them on your whiteboard!

Rate of Reaction

Many factors affect the rate of a chemical reaction, but you are responsible for knowing the 5 listed below:◦Concentration◦Temperature◦Pressure◦Surface Area◦Catalysts

What Affects the Rate of Reaction?

What makes these reactions occur again?◦Collisions between molecules – (molecules are bumping into each other and their valence electrons are bonding leading to a chemical reaction)

And how does this affect the Rate of Reaction?◦More collisions = more reactions at a faster rate

◦Less collisions = less reactions at a slower rate

“Collision Theory”

Use your technology to complete Parts 1-3 on your note guide

You may work with anyone so that you can share technology.

You have 20 minutes

Rate of Reaction WebQuest

Increasing the concentration (amount of a substance) increases the reaction rate…HERE’S WHY:

Packing more particles of a substance into the same amount of space

Causes particles to bump into each other more often (collision theory)

More contact = more reaction taking place

So what does decreasing the concentration do?

Concentration

Increasing the temperature, increases the reaction rate…HERE’S WHY:

Particles speed up, become hyper, move around more

Particles then bump into each other more (collision theory)


So what does decreasing the temperature do?

Temperature

Increasing thepressure, increases the reaction rate…HERE’S WHY:

Particles have less space to move in Particles then bump into each other more

(collision theory) More contact = more reaction taking place

So what does decreasing thepressuredo?

Pressure

Adding a catalyst increase the rate of reaction…HERE’S WHY:

Catalysts act as a “matchmaker” to jump start a reaction or make it faster

Without them reactions would be slower or not happen at all

Catalysts are not affected or used during the reaction – they are still left over

Inhibitors are the opposite – how would you describe/define them?

Catalysts

Increasing the surface area (by breaking something into multiple pieces) increases the reaction rate…HERE’S WHY:

More surface exposed means greater chance for particles to contact each other (collision theory)


Surface Area

Group Leader – manages the group, reads the directions, makes sure everyone records data

Supply Manager – responsible for getting, returning and clean-up of supplies

Data Technician – takes any measurements necessary (temperature) and reports your group’s data to Ms. Sarnelli’s computer

Timekeeper – someone with a timer/stopwatch on their phone to time the reaction

Rate of Reaction Investigations

Send your supply manager to get 2 test tubes - some of you will receive solutions B1 &C and some of you will receive solutions B2 &C

Pour one of the solutions into the other and back again so all of the liquid is in one test tube…START YOUR TIMER IMMEDIATELY!

You must watch your experiment until you see the color change. If you are not paying attention, you will miss it!

Record the reaction times on your data table & decide as a group which factor affected the reaction rate!

Iodine Clock –

Send your supply manager to get your glue/water mixture, Borax and a popsicle stick.

Mix the Borax into the glue/water mixture and stir with the popsicle stick.

The borax DOES NOT BOND with the glue….it bonds the water with the glue, but is not part of the reaction….it is in the leftover liquid –

What role does the Borax play in this reaction?

Flubber

1st Block Data Table (A-day)Independent

VariableWhat is Affecting

the Reaction Rate?

Temperature Time for Reaction to Complete

Powdered AlkaSeltzer Tablet

concentration N/A 55.5 seconds

Broken AlkaSeltzer Tablet

SURFACE AREA

N/A 34 seconds

Whole Alka Seltzer Tablet

Surface Area N/A

Room Temp Water Temperature Room Temp.

Cold Water TEMPERATURE Cold 47

Hot Water Hot 26.26

AlkaSeltzer in Film Canister

Surface area concentration

N/A 12.34 SECONDS

Denture Cleaner in Film Canister

Concentration, pressure

N/A 6 min

3rd Block Data Table (A-day)Independent


the Reaction Rate?


PowderedAlka Seltzer Tablet

surface area N/A 19 seconds

BrokenAlka Seltzer Tablet

Surface area N/A 37 Seconds


concentration N/A 42 seconds

Room Temp Water Temperature Room Temp. 37.39

Cold Water Temperature Cold 50 Seconds

Hot Water Temperature Hot 1 minute 31 seconds

Alka Seltzer in Film Canister

Pressure N/A 7.97 seconds


N/A

4th Block Data Table (A-day)Independent Variable

What is Affecting the Reaction

Rate?



Surface area N/A 25.97 seconds


Surface Area N/A 37 seconds


pressure N/A 34 Seconds

Room Temp Water Surface AreaTemperature

Room Temp. 35 seconds

Cold Water temperature Cold 1 minute and 15 seconds

Hot Water Surface temperature

Hot 13 seconds


pressure N/A 17 seconds


N/A

1st Block Data Table (B-day)Independent


the Reaction Rate?


Powdered AlkaSeltzer Tablet

N/A

Broken AlkaSeltzer Tablet

N/A


N/A

Room Temp Water Room Temp.

Cold Water Cold

Hot Water Hot

AlkaSeltzer in Film Canister

N/A


N/A

3rd Block Data Table (B-day)Independent


the Reaction Rate?



N/A


N/A


N/A


Cold Water Cold

Hot Water Hot


N/A


N/A

4th Block Data Table (B-day)Independent Variable

What is Affecting the Reaction

Rate?



N/A


N/A


N/A


Cold Water Cold

Hot Water Hot


N/A


N/A

Review your Chemistry Vocabulary List so that you are prepared for the “Starburst Speedword” next class, AND the last test!

Homework:

Update your Table of Contents Write your homework – leave it to be stamped

Get your Review Packet out to be checked!

WARM - UP

Date Session#

Activity Page#

10/18 & 10/21

20 Chemistry Review Packet 33

10/22-10/23

21 Starburst Speed Word 34

Let’s Take a Look At Your Data Table…

warm - up

Documents

chemical reaction

reaction rateheres

rate of reaction speed

rate of reactionheres

collision theorymore

chemical equation

number of collisions

spacecauses particles