Question

Question 9(a)
Five solutions A, B, C, D and E when tested with universal indicator showed pH as 4, 1, 11, 7 and 9, respectively. Which solution is
(a) neutral?
Arrange the pH in increasing order of hydrogen-ion concentration.

Answer 1

$pH=-log\left[H^{+}\right]$

Solution D has pH = 7, hence its neutral.
The pH can be arranged in the increasing order of the concentration of hydrogen ions as: 11 < 9 < 7 < 4 < 1.