Waiting for answer This question has not been answered yet. You can hire a professional tutor to get the answer.

QUESTION

# How can I write the formula for aluminum oxide?

The formula for aluminum oxide is Al_2O_3.

The correct answer is Al_2O_3.

Let us see how we got the answer; Look at the electronic arrangement of Al and O atoms.

Al ( Z= 13) has 13 electrons with following electronic configuration. 1s^22s^22p^63s^23p^1

It loses three electron in its 3s and 3p subshell to achieve stability and forms ion Al^(3+).

Al^(3+) = 1s^22s^22p^6

O ( Z=8) on the other hand has eight electrons and wants to gain two electrons to achieve stable noble gas configuration.Oxygen atom on gaining two electrons forms negative oxide ion, O^(2-) ion.

O ( Z=7) = 1s^22s^22p^4

O^(2-) = 1s^22s^22p^6

Three Oxygen atoms gains two electrons each ( total of six) from two Al atoms, each Al atom loses three electrons (total of six) to three oxygen atom , in this process each Al atom becomes Al^(3+) ion and Oxygen atom after gaining two electrons becomes O^(2-) ion.

2Al^(3+) and 3 O^(2-)

or the formula is Al_2O_3.