Mathematical problems. 100g 16% solution, how much water evaporated to become 20% concentration?
100g 16% solution contains 16g solute and 84g water. If a part of water evaporates to 20%, the equation 16÷20%=80 can be obtained.
Wherein the water content is 80- 16=64, and the evaporated water content is 80-64= 16g, that is, 16g of water can be evaporated, so that 100g 16% solution can be changed into 20% solution.