Saline solution

Question

Determine how much water should be added to 2 liters of 4% saline solution to reduce the concentration to 3%

Answer 1

we have 2 Liters of 4% saline

We wish to add pure water to dilute to 3%

 

Since we are adding pure water, we will use the water concentrations to work the problem

 

4% saline is 96% water.

Water concentration is 2(0.96)

To this we add x L of water

These add to (2+x) liters of 97% water = 0.97(2+x)

 

 

2(0.96) + x = 0.97(2+x)

1.92 + x = 1.94 + 0.97x

x - 0.97x = 1.94 - 1.92

0.03x = 0.02

x = 0.02/0.03

x = 2/3 Liters of water