Summer Research Program for Science Teachers

 

Agatha Cadette

Samuel J. Tilden High School

August 2007

 

 

A Reaction Involving Production of a Gas

 

 

 

Objectives:

 

  1. Define properties of gases.
  2. Describe type of reactions.(Decomposition, Synthesis, Single Replacement, Double Replacement)
  3. Apply the law of conservation of mass to chemical reaction
  4. Calculate moles of gas produced.

 

Vocabulary: physical change, chemical change, law of conservation of mass, catalyst, mole calculation

Materials:  Vinegar, baking soda, bubbles machine, splints, matches, digital camera

 

Demonstration:   

(Take pictures during reactions)

 Add vinegar and baking soda to small fish tank.

Observe reaction.

Test for carbon dioxide using a burning splint.

Observe reaction.

Using a bubbles maker, blow bubbles into tank.

Observe reaction.  Question: Explain your observations.

 

1. Show pictures of demonstration while reviewing answers.

 

Summary 1:

 

  1. List the properties of carbon dioxide.
  2. Name the type(s) of reaction.
  3. Write a balanced equation for the reaction.

 

Group Activity:

(Class of 32 students)

 

Introduction:

Hydrogen peroxide slowly decomposes to produce oxygen and water. In this activity yeast is added to speed up the reaction. You will carry out a test to identify the type of gas. Then using your prior knowledge of mole calculation, you will calculate moles of gas produced.

 

 

Group Members:

 

Group Leader: ____________________________

Materials Manager: _________________________

Time Keeper: ______________________________

Recorder: __________________________________

 

Materials: 1 bottle hydrogen peroxide, 8, 25.0 mL graduated cylinder, yeast, 8 electronic balance, splints, matches

 

Procedure:

 

  1. Measure 5.0 ml of hydrogen peroxide in the graduated cylinder.
  2. Zero the balance, and then place the cylinder on the balance.
  3. Add a spatula of yeast to the hydrogen peroxide.
  4. Record the mass of graduated cylinder, hydrogen peroxide and yeast.
  5. Observe the reaction for 5 minutes. Record your observations
  6. Test for oxygen using a glowing splint.
  7. Record the new mass.

 

Questions:

 

  1. Name the type of reaction.
  2. What is the function of yeast in the reaction?
  3. State the law of conservation of mass.
  4. Explain the decrease in mass you observed.
  5. Assuming the reaction is complete calculate the number of moles of oxygen produced in the reaction.( moles= mass/ gram-formula mass)
  6. Write a balanced equation for the reaction.

 

Summary 2: Review answers to above questions.

 

Final Summary

 

  1. What are the gas tests for carbon dioxide, oxygen and hydrogen?
  2. Describe the differences in the properties of the gases produced in the demonstration and activity.
  3. Assuming similar conditions as in activity 1, if carbon dioxide was released instead of oxygen how would mass change? Explain your answer.

 

 

Homework

 

  1. Using one paragraph to describe a catalyst and its function.
  2. Give two other examples of catalytic reactions.

 

Standards Addressed: New York City Performance Standards

S1 Physical Sciences Concepts

S4 Scientific Connections and Applications

S5 Scientific Thinking