Question

Predict how many electrons will most likely be gained or lost by each of the following elements.

Al
I know it loses but how many?

Answer 1

Al is 1s2 2s2 2p6 3s2 3p1

So the outside shell has 3, it will lose 3.

Answer 2

thanks. can u explain that? and how did u know the stuff? like i am confused

Answer 3

The easiest way is to look at the periodic table and find Al in group III or group 13 (depending upon the system in use by your prof). In any event, III means it loses 3 (if group 13, the second number is the one you go by).
The 1s and 2s stuff above is how the electrons are divided by orbitals. You may not have covered that yet.

Answer 4

Yah I don't think we have gotten to the second part but the first makes sense.

Thanks:)

Answer 5

so how would u do it when an element gains. like Cl?

Answer 6

For group I, II, and III, (1,2, and 13) there are 1, 2, and 3 electrons in the outside shell so they lose 1, 2, or 3 electrons.
For groups V, VI, and VII (groups 15, 16, 17) they have 5, 6, and 7 electrons in the outer shell; therefore, the GAIN 3 (starting with 5 to make 8), gain 2 (starting with 6 to make 8), or gain 1(starting with7 to make 8). Group 8 (or 18) already have 8 so those usually don't do either. Group IV (14) is the only one not discussed above so those elements can gain OR lose 4 BUT they usually don't do either; rather carbon etc share electrons to fill their outside shells.