Worksheet

This is for recitation on March 5, 1998

 

  1. What is a calorimeter?

 

 

 

2) q=nCD T

Symbol

Units

q

J

n

mol

C

J/° C× mol

D T (Tfinal-Tintal)

° C

A 15.0 g sample of gold (with a heat capacity of 25.4 J/° C× mol) is heated from 16.1 ° C to 49.3 ° C. Assume that the heat capacity is constant over this range. Calculate the quantity of heat absorbed by the gold.

 

 

 
  1. What is Hess’s Law

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  2. What is the heat of formation of N2(g)

    3.  

  3. Your Boss wants you to make 500 ml of a 10-ppm sodium phosphate solution. What you have to use is l L of 12 M sodium hydroxide, 55 gal of 6 M H3PO4, 4 L of 2 M H2SO4, and any volumetric glassware that you need. You will need to dilute the reactents first because the heat of mixing these together will not be safe. Show the steps you use to make this solution.

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  4. What is the heat of formation of C2H5OH?

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  5. Write the neutralization reactions given the following products:
    1. ammonium nitrate

      2.  

    2. sodium chromate

      3.  

    3. potassium phosphate

      4.  

    4. barium sulfate

      5.  

    5. sodium carbonate

 

 

  1. What concentration would a 10 to 1 dilution of 12 M sodium hydroxide give you?

    2.  

     

  2. What is the combustion reaction of C12H14N2O2 (Abrine)? If you have 2.5 mol of Abrine, and 100 mol of O2 what would be the mass in grams of each of the products. Is this an exothermic or endothermic process?

 

 

 

 

 

 

 

10) Ice melting is what type of process exothermic or endothermic, and is q greater of less then zero.