HELP (⊙﹏⊙)

ITS SCIENCE

Explanation:

the most reactive elements are found in group 7 and Group 1.

they are also called halogens and alkali

the answer to your question is c.

if you read the house of usher you should know that the house was haunted

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.