Question

Considering ionic compounds, what type of elements tend to form cations and why? What type of elements tend to form anions and why? What is the formula for aluminum oxide? Describe or show what happened to the balance electrons of each atom to make the compound.

Answer 1

Electropositive elements or generally metals forms cation.

S-Block elements comprising of Li, Na, K, Rb, Cs etc. have the tendency to lose electron in order to attain inert gas configuration.Thus they form cation. Also, D-Block elements are metallic in nature and thus lose electons in order to attain higher stability by half/fully filled shells. Thus they also form cation.

Non-metals tend to gain electrons to complete their octet( attaiin a noble gas configuration) , hence tends to become an anion. This is due to the fact that they have high ionization energies and high electron affinities( referring to their ability to collect electrons).

Formula for aluminium oxide- Al₂O₃

When a compound is formed, there is complete transfer of balance electron between atoms. The metal loses its balance electron to the non-metal and becomes a cation and subsequently non-metal becomes anion and hence the bonding takes place to make a compound.