Question

Note the pH and pOH values labeled with letters on the pH scale below.

A p H scale is shown, fading from red at the left end to blue at the right. Above the scale, p O H is shown in even increments from 14 to zero, and below the scale, p H is shown in even increments from 0 to 14. Points marked are: A at 1 on the p H scale, B at 7 on the p O H scale, C at 13 on the p H scale, and D at 6 on the p H scale.

Based on log rules and the way pH is calculated, what is the difference in [OH– ] concentration between point A and point B.
101
105
106
107

Answer 1

pH at A = 1 → pOH at A = 14 − 1 = 13 → [OH−]A = 10^(−13) M.
At B pOH = 7 → [OH−]B = 10^(−7) M.
Ratio [OH−]B/[OH−]A = 10^(−7)/10^(−13) = 10^6.

Answer: 10^6.