To solve this problem, we can use the concept of dilution, specifically focusing on the concentration of dextrose in the solution.

Given Data:

• We have 1000 ml of a 5% dextrose solution.
• We want to create a 2.5% dextrose solution by adding 0.9% sodium chloride solution (normal saline).

Let:

• $V$ = the volume of 0.9% saline solution that needs to be added (in ml).
• The final volume of the solution will be $1000 + V$ ml.

Steps:

1. Calculate the total amount of dextrose initially present: $\text{Amount of dextrose} = 1000 \, \text{ml} \times 0.05 = 50 \, \text{ml (dextrose)}$

2. Set up the final concentration equation: Since the final concentration of dextrose needs to be 2.5%, we can write: $\frac{50}{1000 + V} = 0.025$

3. Solve for $V$: $50 = 0.025 \times (1000 + V)$ $50 = 25 + 0.025V$ $25 = 0.025V$ $V = \frac{25}{0.025} = 1000 \, \text{ml}$

Conclusion:

The answer is 1000 ml. Thus, 1000 ml of 0.9% sodium chloride (normal saline) must be added to achieve a 2.5% dextrose solution.

Would you like a more detailed explanation or have any questions?

Here are five related questions to expand your understanding:

1. How would the answer change if a different concentration of dextrose solution were required?
2. How is the dilution formula derived and why does it work?
3. What other medical applications utilize the concept of dilution?
4. How would the solution change if a higher initial volume of dextrose solution was used?
5. Why is it important to match the concentration precisely in medical solutions?

Tip: Always double-check units and concentration requirements in medical calculations to ensure accuracy.