Question

The pH of a particular solution is given by mc031-1.jpg, where x represents the concentration of the hydrogen ions in the solution, in moles per liter.
Which graph models the pH of this solution?

Answer 1

pH(x) = -log10(x). So the graph is the decreasing logarithmic curve with a vertical asymptote at x = 0, passing through (1, 0), positive for 0 < x < 1 and negative for x > 1 (concave up). Equivalently, the curve that goes to +∞ as x → 0+, passes through (0.01, 2) and (10, −1).