Question

You need to deliver 450 ml of 5% glucose. You have on hand a liter of sterile water and a 500-ml bottle of 50% glucose. Which of the following is the correct preparation?

A) Mix 250 ml of sterile water with 250 ml of 50% glucose
B) Mix 450 ml of sterile water with 50 ml of 50% glucose
C) Mix 500 ml of sterile water with 50 ml of 50% glucose
D) Mix 400 ml of sterile water with 100 ml of 50% glucose

Answer 1

To prepare a 5% glucose solution, you should mix 450 ml of sterile water with 50 ml of 50% glucose.

Step-by-step explanation:

To prepare a 5% glucose solution, we can use the formula:

%(Volume of Glucose Solution) X (Concentration of Glucose) = %(Volume of Final Solution) X (Concentration of Final Solution)

Let's use the given options to determine the correct preparation:

1. Option A: Mixing 250 ml of sterile water with 250 ml of 50% glucose yields a final volume of 500 ml and a concentration of 25% glucose. This is incorrect.
2. Option B: Mixing 450 ml of sterile water with 50 ml of 50% glucose yields a final volume of 500 ml and a concentration of 5% glucose. This is the correct preparation.
3. Option C: Mixing 500 ml of sterile water with 50 ml of 50% glucose yields a final volume of 550 ml and a concentration of 4.55% glucose. This is incorrect.
4. Option D: Mixing 400 ml of sterile water with 100 ml of 50% glucose yields a final volume of 500 ml and a concentration of 10% glucose. This is incorrect.

Therefore, the correct preparation is Option B: Mix 450 ml of sterile water with 50 ml of 50% glucose.