Student Number:
a b c d e f g h i
Note: Change any “0” value in your student number to a “7”.
If b ≥ 7, x = 9 If d ≥ 7, y = 5
If b ≥ 4, x = 8 If d ≥ 4, y = 4
If b ≥ 1, x = 7 x If d ≥ 1, y = 3 y
Dilutions
- How much of a x.e % (w/v) stock solution is required to create 20.0 mL of a y.i % (w/v)
solution? [3 marks]
- What is the final concentration of a solution if x.e mL solvent is added to y.d mL of a b.c M
solution? [4 marks]
- How much solvent must be added to b.c mL of a 34.6 % (v/v) stock solution to create at c.d %
(v/v) solution? [4 marks]
Serial Dilutions
- What is the initial concentration of a solution that has a final concentration of 0.dg % (w/v) that has been serially diluted 1/b, then 1/c, then finally 1/d? (3 SD) [5 marks]
- You have an aliquot of cells with a concentration of f.hi x 10 cells/mL.
x
Prepare a serial dilution to create e.f mL with a concentration of c.de x 10y cells/mL.
Include your plan to accurately create this serial dilution. Include all the volumes of solute,
solvent, and total solution. [10 marks]
Standard Curve
You collect the following data from a Spectrophotometer. [2 marks]
Concentration (mg/mL) | % Transmittance | Absorbance |
0.0 | 100 | |
0.625 | 93.7 | |
1.25 | 87.6 | |
2.5 | 76.6 | |
5.0 | 57.8 | |
10.0 | 33.7 | |
20.0 | 11.2 | |
Unknown | cd.e |
𝐴𝐴 = 2 − log (%𝑇𝑇)
- Using graph paper, create a handwritten Standard Curve. [10 marks]
Ensure it is properly labeled and professional in appearance.
Using the % Transmittance data for the Unknown to determine the concentration.
- Using Microsoft Excel, create a table of values and a Standard Curve digitally. [10 marks]
Using the equation from the Line of Best Fit, determine the concentration of the Unknown.
Submit a professional looking Table and Standard Curve.
- Calculate the Percent Error for the Unknown, using the digital data as Accepted Value. (2 SD)
[2 marks]