Ch. 15 solution                        test                  90 points                                                                      honors chem

Show your work in an organized manner, including equation / formula, proper conversion factor(s), equation or formula, and units in your work / answer and the proper number of significant figures in your answer.

1.  Describe how to prepare 125 mL of 275 mM sodium hydroxide using solid sodium hydroxide and water; justify your answer.  [15 points]

2. Describe how to prepare 125 mL of 275 mM potassium hydroxide using a 500.0 mM potassium hydroxide solution and water; justify your answer.  [15 points]

3. The addition of excess sodium carbonate, Na2CO3, to a 75 mL aqueous solution of iron (III) chloride, FeCl3, produces 1.0 grams of a precipitate.  What is the concentration of iron (III) chloride prior to the addition of sodium carbonate ?  [15 points]

4. What is the molarity of ____.  [20 points]

a.  Isotonic solution of glucose – it’s 5.0 % glucose, C6H12O6; assume the density of the solution is 1.01 g / mL

b.  125 mL aqueous solution containing 2.5 grams of sodium carbonate


5. Does urea, (NH2)2CO, dissolve in water ?  justify / rationalize your answer based on concepts taught in class in regards to the “solution process”.  The chemical structure of urea is shown below.

Urea has an important role in the formation of urine by the kidneys.  The dipole moment of urea is not equal to zero.  [10 points]

6. define __  [15 points]

a. equivalence point 

b. end point