Unfortunately, strong and weak mean something totally different in chemistry than the do in regular life. Strong tea, for example, is concentrated tea. In chemistry, that would be "high molarity" tea. "Strong" -- when referring to acids and bases -- actually means something quite different, as explained in this vid.
Ka and Kb: Weak Acid & Base Dissociation Constants
These are basically just equilibrium constants for the special case of weak acids and bases which don't dissociate fully (or much at all) in water. This video covers the use of ICE tables to solve the two major types of problems you might come across.
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