In the previous post, we have discussed on the chemical definitions of BASEs, which are Hydroxides or Oxides that react with Acids to form Salt and Water only.
Now, today we are going to learn on the Chemical Definition of ALKALIS. And this is where many students got confused and lost their way in scoring in this chapter. BEWARE!!!!!
An Alkali is a BASE that is SOLUBLE in water.
Alkaline solutions are produced when alkalis dissolve in water.
One Important point to note is that Alkalis part of the family of BASEs.
In fact BASE comprises of both the Insoluble “BASE” and the Soluble “Alkalis”
This is a misconception that have many students confused and lost. Personally, i dont like the way they repeat the word BASEs twice.
Let’s use an analogy to explain this. BASE is the Father of a family while ACID is the mother of a family. The Son of the family is “Insoluble Base” which carries the family name forever, aka Base..while the daughter of the family is “Alkalis”-a soluble base but does not carry family name forever, and in this case – has the name of “Alkalis”
Some common examples of Bases include the following:
Insoluble Bases:
Magnesium Oxide
Copper (II) Oxide
Lead(II) Oxide
Iron (III) Oxide
Iron (II) Oxide
Soluble Base (aka Alkalis):
Potassium Hydroxide
Sodium Hydroxide
Calcium Hydroxide
Ammonium Hydroxide
Barium Hydroxide
Can you see a trend in both Insoluble Base and Soluble Base (aka Alkalis)??
Insoluble Bases are usually the Metal Oxides while Alkalis are usually the Metal or Ammonium Hydroxides.
Hope you get this clear because it is a important basic concepts that will determine how far you will go for this topic.
PPS: This post belongs to a series of blogposts that is associated with Secrets of “Acids, Bases & Salts and Qualitative Analysis revelaed”
Esraa says
It was very helpful . Thanks.