How do you know if a parent acid/parent base is strong or weak?

Also, how would I find the parent acid/parent base of something? Forexample MgF2? thank you!How do you know if a parent acid/parent base is strong or weak?
Memorize the strong acids:


HCl = hydrochoric acid


HNO3 = nitric acid


H2SO4 = sulfuric acid


HClO3 = chloric acid


HClO4 = perchloric acid


HBr = hydrobromic acid


HI = hydroiodic acid


Memorize the strong bases:


IA %26amp; IIA hydroxides





Virtually all other acids and bases are weak.


Weak acids include:


HC2H3O2 = acetic acid


H2CO3 = carbonic acid


H3PO4 = phosphoric acid


Organic carboxylic acids like citric, tartaric, oxalic, butyric, acetylsalicylic, ....


Weak bases include:


NH3 (or NH4OH) = ammonia (ammonium hydroxide)


Organic amines like aminomethane (CH3-NH2), aminopropane (CH3-CH2-CH2-NH2), ...





MgF2 contains Mg2+ and F-. This salt comes from mixing an acid and a base. Since Mg2+ is positive, it must come from the base, Mg(OH)2. Since F- is negative, it must come from the acid HF.


Mg(OH)2 + 2HF -----%26gt; MgF2 + 2H2O


Base + Acid -----%26gt; A Salt + Water