Question

20. Acid Mixture Bill Charlson needs 10% hydrochloric acid

Answer 1

Answer:

120 ml

Step-by-step explanation:

Let x ml of 5% acid should mix with 60 milliliters of 20% acid to obtain a 10% solution,

Thus, the quantity of resultant mixture = ( x + 60 ) ml,

Also,

Acid in x ml 5% acid + Acid in x ml 5% acid = acid in 10% resultant solution,

5% of x + 20% of 60 = 10% of ( x + 60)

$\frac{5x}{100}+\frac{20\times 60}{100}=\frac{10\times (x+60)}{100}$

$5x + 1200 = 10x + 600$

$5x - 10x = 600 - 1200$

$-5x = -600$

$\implies x = \frac{-600}{-5}=120$

Hence, 120 ml of 5% acid should be mixed.

Answer 2

5% more to the mixture