An uncharged metal sphere hangs by an insulating thread. When you bring a positively-charged rod near, the sphere is pulled toward the rod. But the instant the 2 objects touch, the sphere immediately moves away. Why?

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

the answers are

c and c