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What is 1 + 3?
LC Chem 9.1 pH
The ionic product of water = [H+][OH-]
= [H+] [OH-] at 25°C
Change in Kw with increasing temperature.
Measures the concentration of hydrogen ions in solution
= log10[H+] where the square brackets indicate concentration in moles per litre.
= - log10[OH-]
= pH + pOH
The acid dissociation constant (an accurate measure of the extent to which an acid dissociates) = [H+] [A-] / [HA]
Acids which have relatively large values of Ka (>10^-2)
Acids which have small values of Ka (<10^-2)
The base dissociation constant (an accurate measure of the extent to which a base dissociates)
pH (weak acid)
= -log10 √(Ka x M)
pOH (weak base)
= -log10 √(Kb x M)
Indicator for Strong Acid - Weak Base Titration
Indicator for Weak Acid - Strong Base Titration
3.1 - 4.4
pH range in which Methyl Orange changes colour
Colour of Methyl Orange in Acid
Colour of Methyl Orange in Base
8.3 - 10
pH range in which Phenolphthalein changes colour
Colour of Phenolphthalein in Acid
Colour of Phenolphthalein in Base