Final answer:
To create a 0.90 M solution of H2O2 from a 4.6 M stock solution, a student should measure 9.78 mL of the stock solution and dilute it with water to a total volume of 50.0 mL.
Step-by-step explanation:
To prepare a diluted solution from a concentrated one, we can use the dilution equation M1V1 = M2V2, where M represents molarity and V represents volume. The student is required to prepare 50.0 mL of a 0.90 M solution of H2O2 using a 4.6 M stock solution of H2O2. Applying the dilution equation:
M1V1 = M2V2
Plugging in the given values:
4.6 M (V1) = 0.90 M (50.0 mL)
Solving for V1, we get:
V1 = (0.90 M × 50.0 mL) / 4.6 M
V1 = 9.78 mL
So, the student would need to measure out 9.78 mL of the 4.6 M H2O2 stock solution and add water to bring the total volume up to 50.0 mL to make a 0.90 M solution.