What is the concentration of a new solution obtained by mixing 25ml of water with 125ml of a 20% salt solution in water?

Respuesta :

Given that the concentration of salt in a 125 ml of salt solution is 20%, this means that the ratio of salt to water in the solution is 20 : 80 = 1 : 4.

Thus, the amount of salt in the 125 ml 20% salt solution is given by 20% of 125 = 0.2 x 125 = 25ml and the amount of water in the 125ml 20% salt solution is 125 - 25 = 100 ml.

When 25 ml of water is added to the 125 ml 20% salt solution, the new amount of water is 100 + 25 =125 and the amount of salt remain 25 ml.

Thus, the new volume of the solution is 125 + 25 = 150 ml and the proprtion of salt in the new solution is given by 25 / 150 = 0.1667

Therefore, the concentration of a new solution obtained by mixing 25ml of water with 125ml of a 20% salt solution in water is 16.67%

We want to find the concentration (percentage of salt in volume) in a mix of 25 mL of water an 125 mL of a 20% salt solution.

We will find that the concentration is: 16.7%

Let's see how to get that.

The concentration will be given by the quotient between the amount of salt and the total volume.

The amount of salt will be given by:

s = 125mL*0.2

This is because a 20% of these 125 mL are salt.

And the total volume is just the sum between the volume of water (25 mL) and the volume of salt solution (125 mL)

v = 25 mL + 125 mL = 150 mL

Then the concentration will be:

s/v = 0.2*(125 mL)/(150 mL) = 0.167

Now we multiply this by 100% to get:

0.167*100% = 16.7%

The concentration of the mixture will be 16.7%, so when we mixed the solution with water the concentration decreased, as expected.

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https://brainly.com/question/11868977