Question

If you have you have 30% solution of glucose and you want to make a solution of 3% how would you do it?

A. Add 1 ml of 30% glucose to 10 ml of water

B. Add 1 ml of 30% glucose to 22 ml of water

C. Add 1 ml of 30% glucose to 18 ml of water

D. Add 1 ml of 30% glucose to 9 ml of water

I could use some help with this question.

Answer 1

Add 1 ml of 30% glucose to 9ml of water

In order to solve this, lets consider we have 100ml of 30% glucose solution (30g of glucose in 100ml of distilled water). To make this solution 3%, we will have to dilute it with more water.

30g of glucose in 100ml of water = 30% glucose solution

30g of glucose in 1000ml of water = 3% glucose solution.

We have 100 ml of 30% glucose solution. Adding 900 ml of water will make it 1000 ml of 3% glucose solution.

i.e., 100:900 which is nothing but 1:9 ratio.

So, adding 1ml of 30% glucose solution to 9ml of water will give 3% glucose solution.