I'm totally confused about this question....I don't know what kind of an answer the teacher is looking for. The worksheet has the header "Preparation of solutions for Beer's Law Lab."
That said....here's the question: Describe the preparation of 250.0mL of a 0.10 M sucrose (C12H22O11) stock solution from solid Kool-Aid powder. One serving is 17g, which contains 16 g of sucrose. Use distilled water when actually making the solution.
answer:
Weigh out 17 g Kool-Aid accurately (I would use an analytical balance). That contains 16 g sucrose. How many moles is that? moles = grams/molar mass
Add the powder to a 250 mL volumetric flask, add a little water, swirl until all of the powder is dissolved, then add water to the mark. That will give you M = moles/L soln for the stock solution.
To answer the question, "Describe the preparation of 250.0mL of a 0.10 M sucrose (C12H22O11) stock solution from solid Kool-Aid powder," you will need to follow these steps:
Step 1: Calculate the amount of sucrose needed:
- Determine the number of moles of sucrose required using the molarity and volume of the solution. In this case, 0.10 M refers to 0.10 moles of sucrose per liter of solution. Therefore, for 250.0 mL (0.250 L) of solution, you will need:
Moles of sucrose = Molarity × Volume
Moles of sucrose = 0.10 mol/L × 0.250 L = 0.025 mol
Step 2: Calculate the mass of Kool-Aid powder required:
- Based on the information provided, one serving of Kool-Aid powder contains 16 g of sucrose. To find the mass of Kool-Aid powder needed to obtain 0.025 moles of sucrose, you can use the molar mass of sucrose, C12H22O11.
Molar mass of sucrose = (12.01 g/mol × 12) + (1.01 g/mol × 22) + (16.00 g/mol × 11) = 342.34 g/mol
Mass of Kool-Aid powder = Moles of sucrose × Molar mass of sucrose
Mass of Kool-Aid powder = 0.025 mol × 342.34 g/mol = 8.56 g
Step 3: Prepare the stock solution:
- Measure and weigh 8.56 g of Kool-Aid powder, which contains 0.025 moles of sucrose.
- Add the measured Kool-Aid powder into a suitable container, such as a beaker or a flask.
- Add distilled water gradually while stirring to dissolve the Kool-Aid powder completely.
- Continue adding distilled water until the volume of the solution reaches 250.0 mL.
By following these steps, you will be able to prepare 250.0 mL of a 0.10 M sucrose stock solution using solid Kool-Aid powder.