How much water must be evaporated from 100 gallons of a 10% brine (saltwater) solution to get a 40% brine (saltwater)?

1 Answer
Oct 18, 2015

75 gallons of water

Explanation:

Let

#V_1# be volume of 10 % brine solution

#V_2# be volume of 40 % of brine solution after evaporation of water

Mass of brine in volume of #V_1# = #V_1#*(10/100) = 0.1#V_1#

Mass of brine in 100 gallons of 10 % brine solution = #0.1X100# =10 =

Mass of brine in volume of #V_2# = #V_2#*(40/100) = 0.4#V_2#

Total mass of the salt is constant due to evaporation

0.4#V_2# = 10
#V_2# = 10/0.4 =25 gallons

Volume of water evaporated = #V_1 - V_2#

Volume of water evaporated = 100-25 = 75 gallons