Conclusion to the Methane and Ethyne Gas Production Lab

After completing the Lab you will:

1.) View the Chime Models of the two above molecules and determine the bond length and molecular geometry.

2.) Use the Bond Energy program  to determine the amount of energy produced by each when burned.

Review of Lab Data: What you should have seen!

Substance (gas) Did the gas react with KMO4? How did the gas react when burned?

Methane

No reaction Burned clean.. not very reactive
Ethyne Formed a precipitate Produced a black residue...reacted violently

Conclusion Questions:

1.) From the above lab data, which gas was the most reactive.______________

2.) Click here to determine the formula, Molecular Geometry, and the Bond distance and then complete the following table:

Substance (gas) Chemical Formula Double Bonds? Y/N Molecular Geometry Bond Distance
( in A)
Methane  

 

     
Ethyne  

 

     

3.) Click here to determine the amount of energy produced when methane and ethyne are burned. You will need the Excel program.

    a. How much energy is produced when 1 mole of methane is burned?_____________ Is this reaction exothermic or endothermic? _________________

    b. How much energy is produced when 1 mole of ethyne is burned?_____________Is this reaction exothermic or endothermic? _________________ (** divide answer by 2 as 2 moles are in balanced eq)

    c. Which gas produces the most energy? ________________ Explain why this does/doses not makes senses when compared to the reactivity of the two gases from your lab data?

4.) Compare Bond Length to energy produced. Explain how bond length is related to energy produced for the two gases. Describe in terms of direct or inverse relationships.

   

 

 

Created by: Carol Gregory         Magruder High School             6/25/03

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