Saint Clair College of Applied Arts and Technology
CHM 327
Analytical Chemistry I
Test 1
NAME:___________________________
1. Name two of the three sources of error typically encountered in analytical
chemistry investigations.
(2)
2. Explain in the space provided the difference between constant and proportional
error.
(2)
3. What type of error (determinate or indeterminate) is typically biased or
unidirectional?
(1)
4. Explain in the space provided why indeterminate error cannot be corrected.
(2)
5. What are two sources of determinate method errors?
(2)
6. The standard deviation formula, represented by the term sigma (), “fixes” the
data so that the range that it describes accounts for 68.3% of the measurements
taken. True or false (circle the correct answer).
(1)
7. How many Na+ ions are contained in 5.34 mole of Na3PO4 (MW=163.945 g/mol)
given that 1 mole contains 6.02 x 1023 ions/molecules)?
(4)
8. Find the number of millimoles of solute in 750 mL of 0.0555 M KSCN.
(3)
9. What is the mass in milligrams of 500 mmol of MgO (MW=40.30 g/mol)?
(3)
1
10. What is the mass in milligrams of solute in 6.75 mL of 0.0619 M KNO3
(MW=101.10 g/mol)?
(4)
11. A 12.5% (w/w) NiCl2 (MW=129.61 g/mole) solution has a density of 1.149 g/mL.
Calculate
a. The molar concentration of NiCl2 in this solution.
(4)
b. The molar Cl- concentration of this solution.
(2)
c. The mass in grams of NiCl2 contained in each liter of this solution.
(2)
12. Convert 8.43 x 105 mol to mmol (show your work).
(2)
13. How many millimoles are in 1.25 x 10-3 mole (show your work)?
(2)
14. What KHP mass (MW=204.22 g/mole) is required to neutralize 20.00 mL of
0.1247 M HCl (show your work)?
(4)
2
15. Ten milliliters of a 0.1123 M solution of HCl is diluted in a 100.0 mL volumetric
flask. A solution containing sodium hydroxide (MW=40.00 g/mol) requires 5.76
mL of the dilute HCl for neutralization. How many milligrams of NaOH are in
the sodium hydroxide solution?
(5)
16. Show the overall chemical equation that describes the reaction between sodium
carbonate and hydrochloric acid in aqueous solution.
(4)
17. What indicator would be used to indicate end point for the titration in question #
16? Explain in one sentence why the end point indicator used in question #16
would not be the indicator used for the reaction in question #14.
(3)
18. What Na2CO3 mass (MW=105.9 g/mole) is required to neutralize 22.31 mL of
0.1017 M HCl (show your work)?
(5)
19. 2.5543 grams of Na2CO3 (MW=105.9 g/mole) are placed in a 500.0 mL
volumetric flask. A 25.00 mL aliquot of this solution is neutralized with 17.55
mL of HCl. What is the molarity of the HCl solution (show your work)?
(6)
3