How many ounces of a 40%
hydrochloric acid solution must be
mixed with 12.0 ounces of a 15%
hydrochloric acid solution to make a
30% solution?

The quantity of 40% hydrochloric acid mixed with 12 ounces of a 15%  hydrochloric acid solutions is  18 ounces

Step-by-step explanation:

Given as :

Let The quantity of 40% hydrochloric acid mixed with 12 ounces of a 15%

hydrochloric acid = x ounces

So, Total quantity becomes = ( x + 12 ) ounces

Now, According to question

x × 40% + 12 × 15% = (x + 12) × 30%

Or, x × + 12 × = (x + 12) ×

Or, 40 x + 12 × 15 = (x + 12) × 30

Or, 40 x + 180 = 30 x + 360

Or, 40 x - 30 x = 360 - 180

Or, 10 x = 180

∴   x =

i.e x = 18 ounces

So, The quantity of 40% hydrochloric acid mixed with 12 ounces of a 15%  hydrochloric acid solutions = x = 18 ounces

Hence, The quantity of 40% hydrochloric acid mixed with 12 ounces of a 15%  hydrochloric acid solutions is  18 ounces . Answer