If aluminum (al) and sulfur (s) form an ionic compound, what is the charge on each ion and the formula for the compound?

Al³⁺, S²⁻; Al₂S₃

Explanation:

Al is a metal, so it loses its three valence electrons in a reaction to form Al³⁺ ions.

S is a nonmetal. It needs two more electrons to complete its octet, so it tends to form S²⁻ ions.

We can use the criss-cross method to work out the formula of the compound.  

The steps are

Write the symbols of the anion and cation. Criss-cross the numbers of the charges to become the subscripts of the other ion. Write the formula with the new subscripts. Divide the subscripts by their highest common factor. Omit all subscripts that are 1.

When we use this method with Al³⁺ and S²⁻, the formula for the compound formed becomes Al₂S₃ .

All the elements are arranged by melting points on the periodic table. in row they go from metals to gasses. in the row from sodium to argon, sodium is more reactive than the one on its right, magnesium.

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.