pharmacy calculations: dilutions

What is the purpose of performing a dilution in pharmaceutical preparations?

To achieve a desired concentration for safe administration

When preparing a dilution from a stock solution, which formula is used to determine the appropriate quantities?

Q1 x C1 = Q2 x C2

When performing a dilution, why is it important to know the initial concentration of the stock solution?

To determine the volume of the diluent needed

If you need to prepare 250 mL of a 1:10 dilution from a 1:2 stock solution, how many mL of the stock solution will you use?

50 mL

When diluting a concentrated solution, what is the role of the diluent?

To decrease the concentration of the active ingredient

A 5 mL vial of medication with a concentration of 20 mg/mL needs to be diluted to 5 mg/mL. What will be the final volume after dilution?

20 mL

What does a 1:10 dilution indicate in terms of the amount of solute and solvent?

1 part solute to 10 parts final solution

What is the importance of maintaining a sterile technique during the preparation of dilutions for injectable medications?

To prevent contamination and infection

Which equipment is most appropriate for accurately measuring small volumes of liquid for dilution?

Pipette

Which of the following describes a scenario where dilution is not appropriate?

Increasing the concentration of a solution

Match the following terms with their definitions.

Stock Solution ….The original, concentrated solution before dilution.

Diluent……The substance used to decrease the concentration of a solution.

Dilution ….The process of reducing the concentration of a solution.

Final Concentration ……The concentration of the solution after dilution.

Potency ……..The strength of the active ingredient in a solution.

What is the correct order in the dilution process?

A. Measure the volume of the stock solution

B. Add the diluent to the stock solution

C. Calculate the final concentration

D. Mix thoroughly

E. Label the final solution

C - A - B - D - E

When preparing a dilution, which of the following are most important to ensure accuracy? (Select all that apply)

• Proper measurement of the stock solution

• Accurate calculation of the diluent volume

• Use of calibrated equipment

When calculating dilutions, which of the following components are essential? (Select all that apply)

• Initial concentration

• Final concentration

• Volume of stock solution

Which of the following are reasons to perform a dilution of a stock solution? (Select all that apply)

• To achieve a specific concentration

• To prepare a solution for a specific route of administration

• To improve the stability of the active ingredient