Question

Sodium hydroxide (NaOH) was added to pure water (H2O). Which most likely were the pH values of the water before and after the sodium hydroxide was added to it?

A. before = 7, after = 9
B. before = 7, after = 4
C. before = 4, after = 7
D. before = 9, after = 7

Answer 1

A before = 7, after = 9

Step-by-step explanation:

Answer 2

Before 7 after 9. A pH smaller than 7 indicates acidity with 0 being completely acidic. A pH greater than 7 shows alkalinity with 14 being completely alkaline. 7 is neutral. Since NaOH is alkaline, adding it to a neutral substance would increase the pH and it would increase from 7 to 9.