The pH of a sample of river water is 6.0. A sample of effluent from a food processing plant has a pH of 4.0. What is the ratio of hydronium ion concentration in the effluent to the hydronium ion concentration in the river
A) 1/3 times as acidic
B) 1.5 times more acidic
C) 10 times more acidic
D) 100 times more acidic
E) None of the above

Question

Quizplus · Accepted Answer

The pH scale is logarithmic, which means that each unit of change corresponds to a tenfold change in hydronium ion concentration.

The difference between a pH of 4.0 and 6.0 is two units, which corresponds to a 10^2 (or 100) times difference in hydronium ion concentration.

Therefore, the effluent is 100 times more acidic than the river water, so the answer is D.

The PH of a Sample of River Water Is 6