You need to make 20ml of a 20% glucose solution. The M.W. of glucose is 180.16.
How would you accomplish this:
Glucose _______g
Pure Water _______ml
To make a 20% glucose solution, we need to calculate the mass of glucose and the volume of pure water required.
First, let's determine the mass of glucose needed. The percentage concentration is defined as the mass of solute divided by the total mass of the solution, multiplied by 100. In this case, we know that the solution volume is 20 ml and the percentage concentration is 20%.
Step 1: Calculate the mass of glucose needed:
20 ml × 20% = 4 ml glucose (since the percentage is given as a volume percent)
Step 2: Convert the volume of glucose to mass:
To convert the volume of glucose to mass, we need to know the density of glucose. However, since the molecular weight of glucose is given (180.16 g/mol), we can use that to convert ml to grams.
1 ml of a glucose solution with a concentration of 1 g/ml contains 180.16 g of glucose. So, 4 ml of the solution will contain:
4 ml × 180.16 g/ ml = 720.64 g glucose
We now know that we need to add 720.64 g of glucose to the solution.
Next, we can calculate the volume of pure water required to make the final solution volume of 20 ml. Since we have added 720.64 g of glucose, the remaining volume will be filled with water:
Total volume of solution = volume of glucose + volume of water
20 ml = 4 ml (glucose) + volume of water
So, the volume of pure water required would be:
Volume of water = 20 ml - 4 ml = 16 ml
To summarize, you would need to add approximately 720.64 g of glucose and 16 ml of pure water to make 20 ml of a 20% glucose solution.