A nutritional formula calls for 500 g of dextrose in a total volume of 2000 ml. how many milliliters of a 70% w/v dextrose injection are needed to provide the required amount of dextrose?
This seems to be a dimensional analysis problem. We have:
500g/2000ml
70% w/v = 70 g dextrose/100 ml
Molecular Weight: 1 mmole/180 g dextrose
These are known, yet I am not sure of the set up.
I found out 2000 ml is not necessary knowledge to answer the equation. You simply do the following:
(500g dextrose) * (100 ml solution/70g dextrose) = 714.29 ml
500gm of Dextrose in 2000ml NS
makes it sol of D25%w conc. (25gm in 100ml)
Thus, to provide D70%
25gm =100ml
70= 100/25*70
= 280ml sol to be infused
To solve this problem, we need to find out how many milliliters of a 70% w/v dextrose injection are needed to provide 500 g of dextrose.
Let's set up the dimensional analysis as follows:
First, let's convert the grams of dextrose in the nutritional formula to millimoles:
500 g dextrose * (1 mmole/180 g) = 2.78 mmol dextrose
Next, let's convert the millimoles of dextrose to milliliters of 70% w/v dextrose solution:
2.78 mmol dextrose * (100 ml/70 g) = 3.97 ml of 70% w/v dextrose solution
Therefore, approximately 3.97 ml of a 70% w/v dextrose injection are needed to provide the required amount of dextrose.
To solve this problem using dimensional analysis, we need to set up the conversion factors correctly.
Given:
- Nutritional formula requires 500 g of dextrose in a total volume of 2000 ml.
- 70% w/v dextrose injection contains 70 g of dextrose per 100 ml.
First, let's convert the given requirement of 500 g of dextrose to millimoles (mmol).
1 mmole of dextrose = 180 g
500 g of dextrose * (1 mmole / 180 g) = 2.78 mmol of dextrose
Now, let's determine the volume of the 70% w/v dextrose injection needed to provide 2.78 mmol of dextrose.
Conversion factor: 70 g dextrose / 100 ml
2.78 mmol of dextrose * (100 ml / 70 g) = 3.97 ml
Therefore, approximately 3.97 milliliters of a 70% w/v dextrose injection are needed to provide the required amount of dextrose.