5.
Which of the following equations correctly interrelate pH, pOH, [ H
+
] and [ OH
-
] ?
i) pH = 14 / pOH
ii) [ H
+
] = - log pH
iii) [ OH
-
] = K
w
/ 10
-pH
iv) pOH = - log ( K
w
/ [ H
+
] )
a) ii) only
b) iii) only
c) iii) and iv) only
d) i), ii) and iii) only
e) all of the above
