[Nishka]

This is my first time posting here, not sure where I was supposed to post it. Its also 4 AM so I'm quite tired lol.

Can someone please explain in laymen's terms how Sulfur is -2, +4, and +6? I am supposed to memorize 30 nomenclature terms with the common valence and everything but I don't know how I'm going to do that if the methods of finding each valence differs.

For example, I know the valence of elements like Lithium and Sodium off the top of my head: They are both +1 because they need to lose 1 outer electron to become stable.

That's all fine and everything, but 16 of the elements I'm supposed to memorize I don't have a clue as to how to find it. I've looked all over google and they explain in terms I can't understand and don't relate to the electron shells...

Like seriously, Oxygen is in the same collumn as Sulphur but they're just so different! I expected Sulphur to be just -2, but apparently not.

Other elements that I don't understand:

-Ag
-Zn
-S
-Al
-C
-Cu
-Hg
-Fe
-Sn
-Pb
-Mn
-N
-P
-As
-Sb
-Bi

School in 3 hours, spent two days trying to figure a proper way to memorize this but it doesn't work if I don't understand it. The teacher doesn't answer questions so that's out of the "question". This is my last hope, I need a 90% to pass (27/30). If not, I automatically fail and I'll have to restart another time.

So yeah, if all else fails, just a memory tool would be enough for me. If anyone answers this, thank you.

[Hunter2]

Main thing is you have to learn and understand the periodic table of elements.
It has groups

Elements in depending in group 1 to 3. loose 1, 2 or 3 electron to get the stable value and form Me⁺, Me²⁺ and Me³⁺
Elements from group 4 to 7 can either loose also electrons but also can get electrons what give negative values
In you case sulphur can either -2 but also + 4 and + 6 to tell the common oxidation stages. Others between also possible.
The periodic system of elements also contain sidegroups,
Do you know the built up of atoms, the term of orbitals, etc.
At least you have to learn the elements. The side elements can have mostly stable +2 or +3 but depending which one all oxidation stages possible like manganese +2,+3,+4,+5,+6 and also +7.
The side elements also in groups, forexample silver is in sidegroup 1 what means it is Ag⁺, zinc in sidegroup 2 what means Zn²⁺

Try to check your list and look them up, then you know at least one oxidation stage.

[Shipwreck]

Ok, first thing's first. Let's get your terminology straight.

An atom's Valence refers to the number of bonds the atom typically forms in a molecule. I.e. hydrogen atom has a valence of 1 because it can form one bond with another atom (i.e. hydrogen fluoride H-F).

An atom's oxidation state refers to how the atom might behave in a particular molecule given its electron configuration. Oxygen, for example, almost always (except in peroxides...a story for another day) has an oxidation state of -2. In other words it hogs two electrons from other atoms

The column you referred to is called a group. A row is called a period (hence "periodic" table).

Unfortunately for you, you really do need to grasp the basic concept of electron shells in order to understand why certain atoms have multiple oxidation states and I strongly suggest reading these sections from your textbook before you go any further. But you also need to understand the concept of electronegativity. Electronegativity refers to the tendency of an atom to hog not just its own electrons, but the electrons of other atoms as well. The most electronegative atoms are located in the top right of the periodic table (i.e. O, F, etc.). Electronegativity tends to decrease as you move down and to the left of these elements. Oxygen, for example, almost always has an oxidation state of -2 because it is one of the most electronegative elements and therefore will always try to hog 2 electrons from other atoms in order to complete its octet.

Sulfur, on the other hand, is not as electronegative as oxygen (because it's lower down on the periodic table), even though both are located in the same group in the periodic table. We know that sulfur can have an oxidation state of -2 just like oxygen because it "wants" 2 more electrons in order to complete its outer electron shell. However consider the molecule sulfur dioxide (SO₂): which element in this molecule is MORE electronegative? Oxygen. So which atoms are going to be hogging the electrons? The oxygens. Each oxygen atom will hog 2 electrons from the sulfur atom in order to complete its octet, and since there are 2 oxygen atoms in total in the molecule, the total number of electrons being "hogged" is 4 (2 oxygens x 2 electrons being hogged = 4). We know that elemental (neutral) sulfur has 6 valence electrons in its outer shell, but it will "lose" 4 of these to the oxygen atoms, giving it an oxidation state of +4.

In theory, nearly all elements towards the top right-hand side of the periodic table have multiple oxidation states, but the atom's electronegativity and other factors not discussed here have an influence on this. Chlorine (Cl), for example, has oxidation states of -1 (as you would expect), but also +1, +2, +3, +4, +5, +6 and +7.

My guess is that your teacher wants you to be able to recognize the most commonly observed oxidation states for certain elements. I highly doubt that he/she wants you to memorize EACH and EVERY single oxidation state which has ever been observed during chemical experiments for every element in the periodic table. What's important is that you understand how octets are formed and how atoms typically behave in bonds. And, not that it is any of my business, but in the future I would avoid trying to figure this stuff out at 4am the day before an exam. Just a thought...