Question

Salt is added to water and the mixture is stirred until no more salt dissolves. The salt that does not dissolve is allowed to settle out. What happens to the concentration of salt in solution if water evaporates until the volume of the solution is half the original volume? (Assume temperature remains constant.)

Answer 1

Answer:

The final concentration of salt in the solution will be two times the initial concentration.

Explanation:

The solution will have 2 times the original initial concentration because we will lose the half of the water of the initial volume. To solve this question we can use a formula called dilutions formula.

$V_{1}$x$C_{1}$=$V_{2}$x$C_{2}$

The V1 and C1 belongs to the initial values and the V2 and C2 belongs to the final values so knowing that the V2 is the half of V1 we can write the next expression.

$V_{2}$ = $V_{1}$/2

And if we replace this expression in the initial equation we obtain:

$V_{1}$x$C_{1}$= $V_{1}$/2x$C_{2}$

Then we pass the equal terms to one side of the equation:

2$V_{1}$x$C_{1}$/$V_{1}$=$C_{2}$

Finally we cancelled the common terms in this case V1 and we obtain that:

2$C_{1}$=$C_{2}$

That means the final concentration will be 2 times the initial concentration.