Question

A science teacher has a supply of 5% hydrochloric acid and a supply of 65% hydrocloric acid (HCI). How much of each solution should the teacher mix together to get 42 mL of 45% HCI for an experiment?

A) The teacher will need 14 mL of the 5% solution and 28 mL of the 65% solution.

B) 28 mL of 5% solution and 14 mL of the 65% solution

C) 14 mL of the 5% and 14 mL of the 65% solution

D) 28 mL of the 5% solution and 28 mL of the 65% solution

Answer 1

the answer would be d

Answer 2

Answer: The teacher will need 14 ml of the 5% solution and 28 ml of the 65% solution.

Explanation:

Since we have given that

There has a supply of 5% hydrochloric acid and a supply of 65% of hydrocholric acid.

The teacher needs to mix together to get 42 ml of 45% of hydrochloric acid for an experiment.

So, we will use "Mixture Allegation" to find the quantity of each solution,

Ist type of supply of HCL IInd type of supply of HCL

5% 65%

45%

----------------------------------------------------------------------------------------------

65%-45% : 45%-5%

20% : 40%

2 : 4

1 : 2

So, there is total quantity of mixture = 42 ml

So, Quantity of 5% solution will be

`(1)/(3)* 42=14\ ml`

Quantity of 65% solution will be

`(2)/(3)* 42=28\ ml`

Hence, the teacher will need 14 ml of the 5% solution and 28 ml of the 65% solution.