Help with bonding and chemical formulas?

Question

i dont have time to explain much but im trying to figure out thing about gaining electrons and losing them.like...

Element:Aluminum
Electrons in Outer Level:3
Charge on Ion: ? <----- thats what i wanna know.how can i do it?

another one...

Element:Magnesium
Electrons in Outer Level:2
Charge on Ion: ?

By the way,these give up electrons when they form compounds.
Now, i need help that gain electrons when they form compunds...

Chlorine
Electrons in outer level:7
charge in ion:?

and so on.
can anyone help me how to figure it out with the rest? thanx

Im not sure if mine's right...

Element:Sodium
Electrons in Outer Level:1
Charge on Ion: +1

correct me if im wrong

Answer 1

One can determine the charge an ion will make by its position on the periodic table, except for the transition metals.

Most periodic tables list the transition metals as columns 1B-10B and the metals as columns 1A-2A and then 3A-8A on the right side.
The numbers refer to the number of electrons in the outermost (valence) shell. Remember that all periods except for period 1 (row 1) want to have 8 (or zero) electrons in their valence shell. That means that column 1A will make a +1 charge (will lose 1 e-), column 2A will make +2, column 3A will make +3. Column 7A will gain 1 e- to make 1- ion, column 6A will make 2- and column 3A will make -3.

Knowing this will make your life in chemistry much easier.

Answer 2

there are a few easy ways to do this. elements that has four or less electrons in their valence shells are more likely to lose/give away their electrons. therefore their ionic charge would be +. therefore magnesium would lose their electrons, making them positive, so usually they have +2 ionic charge.

Aluminium would usually have a charge of +3.

Now, elements that have electrons of four and above in their valence shells would more likely take in electrons, so they would have a -charge. so chlorine, in order to complete 8 electrons in its shells, would require 1 electron, so it will have a -1 charge.

note that all elements, when in ion form, tries to stabilise itself by completing itself, which is to have 8 electrons on it outermost shell. so just by checking that, u know how to find its ions. if u cant find one element, check the other elements in its compounds. in one compound, the overall charge would be 0.

take magnesium oxide. Oxygen has 6 electrons in its outer level. therefore its likely to take in 2 electrons to complete 8. so its charge is -2. Magnesium has 2 electrons in outer shell. the easiest way to get 8 in its outer shell would be to throw away the 2 electrons that it has, and go down its other shell, which has 8 already. so magnesium would have a charge of +2.

therefore, magnesium + oxygen
+2 -2 = 0 charge.

remember: lose electron= +charge
gain electron= - charge

Answer 3

the number of electrons in the outer most orbit represent the charge