Question

What is the atomic structure of $ A{l^{3 + }} $ ?

Answer 1

Hint: Atomic structure is defined as the structure of the atom which includes the number of neutrons, number of electrons, and number of protons present in the atom. Electrons are negatively charged particles that revolve around the nucleus, which is present at the centre of an atom.

Complete answer:
Aluminium has atomic number 13, so to attain noble gas configuration aluminium loses three electrons leading to the formation of $ A{l^{3 + }} $ cation. For calculating the number of neutrons, electrons, and protons in $ A{l^{3 + }} $ cation:
Step 1: Calculation of the number of neutrons:
 For calculating the number of neutrons for any cation or an atom, the difference between the mass number of the atom or cation and the atomic number gives the number of neutrons. So, the mass number of $ A{l^{3 + }} $ + is 27 grams whereas the atomic number of $ A{l^{3 + }} $ cation is 13. Therefore, the number of neutrons in $ A{l^{3 + }} $ ion is
 $ 27 - 13 = {\text{ }}14 $
Hence, 14 electrons are present in $ A{l^{3 + }} $ ions.
Step 2: Calculation of the number of electrons:
For calculating the number of electrons in an atom is equal to its atomic number but for cation, the number of electrons is equal to the difference between the atomic number and the number of electrons lost. So, the number of electrons in $ A{l^{3 + }} $ is
 $ 13 - 3 = 10 $
Therefore, 10 electrons are present in $ A{l^{3 + }} $ ions.
Step 3: Calculation of the number of protons:
For calculating the number of protons in an atom or cation, the number of protons is equal to the atomic number. Therefore, the number of protons in the $ A{l^{3 + }} $ ion is 13.
Step 4: Stating the electronic configuration:
Electronic configuration of Aluminium is $ 1{s^2}2{s^2}2{p^6}3{s^2}3{p^1} $ .
After removing three electrons the electronic configuration of $ A{l^{3 + }} $ ion is $ 1{s^2}2{s^2}2{p^6} $ .

Note:
 $ A{l^{3 + }} $ cation is formed by the removal of three electrons from the aluminium atom, with a +3 charge. An aluminium cation is a monatomic trication. Metals are electropositive i.e. they lose electrons to form a positively charged cation. Aluminium ions are silvery and protected by an oxide coating.