Weak Acids

A weak acid is one that only WHAT in water to form H3O+ ions

A weak acid is one that only PARTIALLY IONIZE in water to form H3O+ ions

Most ionize are WHAT

<50% more reactants than products

Ka value is WHAT

Small (<1)

To calculate pH, you need to use the WHAT… you cannot use just the WHAT because it is not WHAT

To calculate pH, you need to use the Ka VALUE… you cannot use just the [WA] because it is not 100% IONIZED

The Ka law is an WHAT

Equilibrium law and devise the same way we did it for Kc

What is the Ka for:

HA (aq) + H2O (l) →← H3O+ (aq) + A-(aq)

Ka = [H3O+(aq)] [A-(aq)] / [HA(aq)]

You will be required to figure out the WHAT before you can calculate the pH

You will be required to figure out the [H3O+(aq)] before you can calculate the pH

You have the WHAT and the WHAT value but you don’t have the WHAT

You have the [HA(aq)] and the Ka value but you don’t have the [A-(aq)]

Since the mole ratio is for [H3O+(aq) : [A-(aq)] is WHAT, they have the same WHAT (this is a WHAT)

Since the mole ratio is for [H3O+(aq) : [A-(aq)] is 1:1, they have the same [ ] (this is a IONIZATION)