What is the relationship of the concentration of H3O and of OH
Hi Dee, this is ez!
H3O+ is an hydronium ion, a Lewis acid and OH-, hydroxide ion is a Lewis base.
Reaction between hydronium and hydroxide yields water molecules
H3O+ + OH- ----> 2H2O
This is called a neutralization reaction.
Another relationship is
(H3O^+)(OH^-) = Kw = 1E-14 @ 25 C.
The relationship between the concentration of H3O+ (or simply H+) and the concentration of OH- ions in a solution is described by the concept of pH and pOH.
To understand this relationship, we need to introduce the concept of the equilibrium constant for the ionization of water, known as Kw. In pure water, a small fraction of water molecules dissociate into H+ and OH- ions in a reversible reaction:
H2O ⇌ H+ + OH-
At 25 degrees Celsius, Kw has a constant value of 1.0 x 10^-14 mol^2/L^2, which means the product of the concentration of H+ ions and OH- ions in water is always equal to this value.
If we define the concentration of H+ ions as [H+], and the concentration of OH- ions as [OH-], we can write the equation for Kw as:
Kw = [H+] x [OH-]
Through algebraic manipulation, we can rearrange this equation to solve for [H+] or [OH-] in terms of the other ion concentration:
[H+] = Kw / [OH-]
[OH-] = Kw / [H+]
By plugging in the value of Kw, we can calculate the concentration of either H+ or OH- given the concentration of the other ion.
Now, let's relate this to pH and pOH. The pH scale is a logarithmic scale that measures the acidity or alkalinity of a solution based on the concentration of H+ ions. The pH is defined as the negative logarithm (base 10) of the H+ concentration:
pH = -log[H+]
Similarly, the pOH scale measures the concentration of OH- ions in a solution. The pOH is defined as the negative logarithm (base 10) of the OH- concentration:
pOH = -log[OH-]
Since Kw is a constant value, pH and pOH are related as follows:
pH + pOH = 14
This equation indicates that the sum of the pH and pOH for any aqueous solution at 25 degrees Celsius is always equal to 14. Therefore, as the concentration of H+ ions increases, the pH decreases, and as the concentration of OH- ions increases, the pOH decreases.