17. pH = 3.00

3.00 = -log [H₃O⁺]

-3.00 = log [H₃O⁺]

this means that the exponent of 10 is -3 and the coefficient should be expressed to two significant figures.

[H₃O⁺] = 1.00 X 10^-3

pOH = 14.00 - 3.00 = 11.00

[OH^-] = - antilog [11.00] = 1.00 X 10^-11

The pH Scale