Name:
Charity Flosser
Date: 12.17.2012
Unit: Lesson: Unit 4 Lesson 11
Classifying Reactions
Objectives:
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Identify the four most common types of reactions: synthesis, decomposition,
single replacement, double replacement
Predict the products of reactions
Balance chemical equations
Part I: Reaction between zinc and iodine
Watch the Video.
http://www.youtube.com/watch?v=xT9V7Y1iKYc
Observations:
Describe what happened when the water was added.
A reaction happened and the iodine exploded into a purple gas
Questions and conclusions:
1. Balance the equation, if necessary, for the reaction between zinc and iodine.
Zn + I2  ZnI2
It is balanced
2. Classify the reaction that occurred between the zinc and iodine.
redox
3. What evidence was there that a reaction took place?
The explosion
1
Part II: Decomposition of hydrogen peroxide
Watch the Video.
http://www.youtube.com/watch?v=kLagq1koOUk&feature=related
Observations:
Describe what happened to the hydrogen peroxide when the manganese dioxide was
added
It formed water and oxygen
Questions and conclusions:
1. The MnO2 was a catalyst and did not get used up in the reaction. Balance the equation,
if necessary, for the breakdown of hydrogen peroxide.
H2O2  H2O + O2
2H2O2 -> 2H2O + O2.
2. Classify the reaction that occurred as hydrogen peroxide was broken down.
Decomposition
3. What evidence was there that a reaction was taking place?
There was a gas that was produced
Part III: Reaction between zinc and hydrochloric acid
Watch the Video.
http://www.youtube.com/watch?v=5p540KucRc8&feature=related
Observations:
Appearance of penny after 4 hours ___________________________
Questions and conclusions:
1. Balance the equation, if necessary, for the reaction between zinc and hydrocloric acid.
Zn + HCl  ZnCl2 + H2
2
2. Classify the reaction between zinc and hydrocloric acid.
3. What evidence was there to indicate that a reaction was taking place?
Part IV: Reaction between potassium chromate and silver nitrate
Watch the Video.
http://www.youtube.com/watch?v=opY3FLrPTa4
Observations:
Appearance after initial mixing _________________________________
Questions and conclusions:
1. Balance the equation, if necessary, for the reaction between potassium chromate and
silver nitrate
K2CrO4 + AgNO3  KNO3 + Ag2CrO4
2. Classify the reaction between potassium chromate and silver nitrate.
3. What evidence was there to indicate that a reaction was taking place?
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