Answer:
The auto-ionization of water is represented by the equation:
H
2
O
⇌
H
+
+
OH
−
H
2
O⇌H
+
+OH
−
In pure water at 25°C, the concentration of
H
+
H
+
ions and
OH
−
OH
−
ions are equal, each being
1.0
×
1
0
−
7
1.0×10
−7
M. This corresponds to a pH of 7 (neutral pH).
However, when a salt like KI is dissolved in water, it does not directly contribute
H
+
H
+
or
OH
−
OH
−
ions to the solution. Therefore, the pH of a solution of KI would remain close to 7, assuming the water itself is pure and not acidic or basic.
Given that KI does not directly impact the pH, the pH of a 0.15 M KI solution would be close to 7, assuming the water used to make the solution is neutral.
