Question

Which solutions are acidic? (Assume all solutions are at 25°C. Kw = 1.0 x 10-14 at 25°C.)

A. A solution with [H+] = 9.4 x 10-6
B. A solution with [H+] = 5.5 x 10-10
C. A solution with pH = 6.1
D. A solution with [OH-] = 6.4 x 10-7
E. A solution with [OH-] = 2.0 x 10-6

Answer 1

All solution are acid that have (H^+) = 1 x 10^-7 or greater or pH smaller than 7.0
For those with OH, you can do
H^+ = Kw/(OH) OR
if OH is 1 x 10^-7 or greater it is basic