CHM1045
Fall 1999
Dr. Michael Blaber

Name_______________________________

SS#________________________________

Exam #1 100 points total

Wednesday September 22 1999

  1. Indicate whether the following are most likely a pure substance, a homogenous mixture or a heterogenous mixture (5 points)

    2. a. Potting soil

    b. Non-iodized table salt

    c. A paperclip

    d. Gatoraid

    e. The gold in Fort Knox

      

  2. Indicate whether the following represent physical or chemical changes (5 points)

    3. a. Toasting a bagel until it is nice and brown

    b. Melting butter on a hot bagel

    c. Burning gasoline in your car engine

    d. Recycling glass

    e. Making wine

      

  3. In the following diagram, the particles from a cathode ray tube are coming directly towards you. In which direction would you expect the particles to be deflected in response to the magnetic field? (write the appropriate letter). (5 points)

    4.  

     

  4. For the following elements, write down the most likely ionic form (5 points)

    5. a. Br

    b. Al

    c. Se

    d. K

    e. Ca

      

  5. Write the balanced chemical equation for the combustion of hexanol (C6H14O) (5 points)

    6.  

     

     

     

     

     

     

     

     

  6. Magnesium can burn in air to produce Magnesium oxide. Write the balanced chemical equation for this reaction and predict two other elements which might be expected to participate in a similar type of reaction with air (10 points)

    7.  

     

     

     

     

     

     

     

     

     

  7. What is the percentage by mass of C, H and O in acetic acid (i.e. vinegar: C2H4O2)? (10 points)

    8.  

     

     

     

     

     

     

     

     

  8. How many grams are there in 3.98 moles of the following compound: (10 points)

 

 

 

 

 

 

 

  1. A certain combustible compound, containing C, H and O atoms, is 65.7% C, 12.4% H and 21.9% O by mass. The experimentally determined formula weight is 146 amu. What is the empirical and chemical formula for this compound? (10 points)

    2.  

     

     

     

     

     

     

     

     

     

      

     

     

  2. Hexane has the formula C6H14 and can be combusted in the presence of oxygen. If 8.0 g of hexane is combusted in the presence of 5.2 g of O2, what is the limiting reagent? How many grams of water will be produced? (Be sure to show the balanced equation for this reaction). (20 points)

    3.  

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

  3. What is the molarity of a 3.5 liter solution of water containing 84.5 g of Ammonium Sulfate (NH4)2SO4? (5 points)

    4.  

     

     

     

     

     

     

     

     

     

  4. You have a stock solution of 5.0 M NaCl and some pure water. How would you use these to produce 4.2 liters of a 0.15 molar solution of NaCl (state exactly how much volume of each you would use)? (10 points)