What is a strong base? What is a weak base?

Question

i know i've already asked this question but i didn't really get a good answer... so what is a strong and weak base? and what is the major difference between them? please help.

Answer 1

A strong base is one that ionizes completely when in water. The best rule to go by is that all alkali metals form strong bases, and the first three alkaline-earth metals form strong bases.

A weak base is one that does not ionize completely when in water. Those are all the other hydroxides not mentioned above.

Answer 2

In chemistry, a weak base is a chemical base that does not ionize fully in an aqueous solution. This results in a relatively low pH level.Weak bases exist in equillibrium much in the same way as weak acids do, with a Base Ionization Constant (Kb) indicating the strength of the base. For example, when ammonia is put in water, the following equillibrium sets up: NH3 + H2O ↔ NH4+ + OH- Kb = [OH-][NH4+]/[NH3]

A strong base is a basic chemical compound that is able to deprotonate very weak acids in an acid-base reaction. The strength of a base is indicated by its pKb value, compounds with a pKb of less than about 1 are called strong bases. Common examples of strong bases are the hydroxides of alkali metals and alkaline earth metals like NaOH and Ca(OH)2.

Answer 3

There are two definitions for Acids and Bases... Bronsted-Lowry and Lewis definitions.

I've been studying Chem for years and I still get confused on this! So don't worry about it, it comes with time.

Strong acids and bases react all the way. That is what you need to get in your head. They will react completely, while a weak base will find an equilibrium and not react completely.

If I remember correctly there are 6 or 7 strong bases that you can just memorize.

Answer 4

strong base:- a base that dissociates completely into a metal ion and hydroxide ion (or nearly so) in aqueous solution.
week base:- a base that dissociates only slightly in aqueous solution.