For each [H30+], determine the pH and state whether the solution is acidic or basic.

(a) [H3O+] = 0.0025 M

(b) [H3O+] = 1.8 × 10−12 M

(c) [H3O+] = 9.6 × 10−9 M

(d) [H3O+] = 0.0195 M

Solution: Here, we are going to determine the pH of the given solutions and classify the solutions as acidic, basic or neutral.

Step1:

pH is the negative logarithm to base 10 of hydrogen ion concentration.

pH = - log[H3O+ ]

We can distinguish acidic, neutral and basic aqueous solutions by the relative values of their pH

Acidic: pH < 7

Neutral: pH = 7

Basic: pH > 7

Step2:

Given, [H3O+] = 0.0025 M = 2.5 x 10-3 MTherefore, pH = - log[H3O+ ]

= - log (2.5 x 10-3)

= - log 2.5 - log 10-3

= - 0.398 + 3

= 2.602

Thus, pH = 2.602

Since, pH < 7, therefore the solution is acidic.

b) Given, [H3O+] = 1.8 x 10-12 M

Therefore,...