Chapter A.8, Problem 41AYU

To determine

To find: How much water must be evaporated?

Answer to Problem 41AYU

Evaporate $10.66$ ounces of water.

Explanation of Solution

Given:

How much water must be evaporated from 32 ounces of a $4\%$ salt solution to make a $6\%$ salt solution?

Calculation:

Let $x=$ amount of water that must evaporate.

Now we know that the amount of pure salt in the original solution $\left(0.04\right)\left(32\right)$ has equal the amount of pure salt in the final solution after evaporation has taken place $\left(0.06\left(32-x\right)\right)$.

So, $\left(0.04\right)\left(32\right)=\left(0.06\left(32-x\right)\right)$.

$1.28=1.92-0.06x$

$-0.64=-0.06x$

$x=10.6667$

Therefore evaporate $10.66$ ounces of water.