Question

What is the chemical formula for the combination of aluminium and phosphorus?

Answer 1

Hint: In the formed compound, aluminum will lose 3 electrons to phosphorus and become positively charged and phosphorus will gain 3 electrons to become negatively charged. Thus the compound aluminium phosphide will be formed.

Complete answer:
The chemical formula of aluminum and phosphorus is called aluminium phosphide \[\left( AlP \right)\] .
Now, let us see how it is prepared and what the reason behind its composition is.
First let us state the atomic number of aluminium and phosphorus. The atomic number of aluminium is 13 and the atomic number of phosphorus is 15.
Thus, aluminium has 3 electrons in its outermost orbit and thus an aluminium atom has to lose three electrons to become a stable atom. Similarly, phosphorus has 5 electrons in its outermost orbit and thus a phosphorus atom has to gain 3 electrons to become a stable atom.
So, one aluminium combines with one phosphorus to form aluminium phosphide. The chemical reaction of formation of aluminium phosphide is given below.
\[4Al+{{P}_{4}}\to 4AlP\]
So, in this reaction 4 atoms of aluminium lose 12 electrons and phosphorus gains 12 electrons.
The name aluminium phosphide has been given to this compound as aluminium loses 3 electrons and phosphorus gains 3 electrons.

Note:
This inorganic compound is highly toxic for human beings and is used in insecticides. Thus, it is banned in some of the countries.
You have to know the atomic number of both of the elements to know about their valence electron and how they would react with each other.