Everything is neutral. Touch a table, a chair, a desk, a tree, and you don't get a shock. Compounds are neutral. So Al2O3 must be neutral. Al has a valence of +3. Oxygen has a valence of -2. Now, let's add the charges.
2 Al @ +3 each is +6.
3 O @ -2 each is -6.
So we have 6 + charges and 6 - charges. They add to zero. Another example.
NaCl. Na is +1. Cl is -1.
Those add to zero.
can anyone help?
aliminium oxide AI2O3, how do they come to this formula when Aliminium has a valency of +3 and oxygen has a valency of -2?
Please help :)
To determine the formula for aluminum oxide (Al2O3), you need to account for the charges of the individual elements and ensure that the combined charges result in a neutral compound.
First, note that aluminum (Al) has a valency or charge of +3, meaning it tends to lose 3 electrons to obtain a stable configuration. On the other hand, oxygen (O) has a valency or charge of -2 since it typically gains 2 electrons to achieve stability.
To balance the charges in the formula, you need to find the smallest whole number ratio that cancels out the charges. In this case, the smallest common multiple of 3 (+3 for Al) and 2 (-2 for O) is 6.
By writing Al2O3, you imply that there are 2 aluminum atoms, each with a charge of +3, giving a total positive charge of +6 (2 x +3). Similarly, there are 3 oxygen atoms, each with a charge of -2, resulting in a total negative charge of -6 (3 x -2).
The combination of 2 aluminum atoms carrying a +6 charge and 3 oxygen atoms contributing a -6 charge leads to a neutral compound with no overall charge, which is what is observed in most compounds.
Therefore, Al2O3 represents the correct formula for aluminum oxide, indicating the presence of two aluminum atoms for every three oxygen atoms.