1457 (2.2x10^-8) follow up question: identify the following as acidic, basic or neutral: ph = 4.56 ph = 10.4 [oh-] = 2.4x10-8 reply quote select: all none message actions expand all

(a) pH = 4.56 is acidic

(b) pH = 10.4 is basic

(c) [OH-] = 2.4x10-8, thus is acidic

Explanation:

The pH is the mesure of the acidity or bacisity of a solution. It indicates the concentration of protons in a solution and it is define as:

The scale of pH goes from 1 to 14, being 1 the most acid condition and 14 de most basic condition. Also a pH = 7 is a neutral condition.

Therefore, if the pH is:  1 ≤ pH < 7 the solution will be acidic and if the pH is 7 < pH ≤ 14 the solution will be basic.

To answer (c) it is also necessary to consider the water autoionization to calculate the protons concentration as shown bellow

For (c) [OH-] = 2.4x10-8

And using the definition of pH