Qualitative Analysis
Sometimes we
need to identify what substance we have from its property. That reason makes us
have to know the properties of chemical substances around us. Here are some
examples of qualitative analysis data from Cambridge International Examination
Chemistry A Level.
Explaining:
From the
table, we can conclude that there are differences when we react the cations
with strong or weak base. For example is: Aluminium.
Al3+(aq)
+ 3OH-(aq) <--> Al(OH)3(s)
In excess of
NaOH, aluminium will form [Al(OH)4]- that reduces the
concentration of hydroxide and make the equilibrium shifts to left so that the
precipitate soluble in excess.
Meanwhile,
in excess of NH3, aluminium won’t form the complex compound. The
excess will shift the equilibrium to right so that there are more precipitate
formed.
0 Response to "Qualitative Analysis "
Posting Komentar