How can you tell an elements oxidation number by looking at the periodic table?

Answer 1

1. Elements on their own have an oxidation # equal to 0.

(ex. in the chem equation Ca + 2AgCl --> CaCl2 +2Ag, Ca and 2Ag would have oxidation #s equal to 0.)

2. Ions in ionic compounds have an oxidation # equal to their charge.

(ex. in the chem equation Ca + 2AgCl --> CaCl2 +2Ag, 2AgCl = Ag+1 and Cl-1, and CaCl2 = Ca+2 and Cl2-1.)

Answer 2

An oxidation state is the sum of - and + charges in an atom, which represents the number of electrons it has donated or accepted. Unreacted atoms have an oxidation number of zero, which means they are neutral. The protons (+) in the nucleus balance out the electron cloud (-) that surrounds it. When an atom loses an electron it will have more protons than electrons and will become positive. This ion has an oxidation number of +1. If an atom accepts an electron it will become negative, and will gain an oxidation number of -1. Compounds will have a net charge of zero and ions have the charge on the ion. This enables you to calculate the oxidation number for atoms that have variable oxidation numbers.

Answer 3

Well, the oxidation number is the number it takes to get to either 0 valence electrons or 8 valence electrons. Say we had the atom...Hydrogen. It has 1 valence electron, so it only take 1 to get to zero. Therefore, the oxidation number would be +1.

Answer 4

1.oxidation number of pure element is zero 2.oxidation number of an ion forms by a single atom is equal to charge of ion. 3.oxidation number of Hydrogen is 1 when it combines with non metals.-1 when combines with metals. 4.Oxidation number of oxygen is 2 only in F2O. -1/2 in superoxide. -1 in peroxides.In all other compounds Oxygen has -2. 5.Exept hydrogen all other group(i) elements show 1 in all compounds.Group(ii) shows 2 and group(iii) shows 3 in all compounds. 6.oxidation no of halogens when they form compounds with H and metal is -1. 6.Sum of oxidation number in a neutral compound is equal to zero.It is equal to charge when an ion is concerned.

Answer 5

To figure out an oxidation number, you must locate which family the specific element is in that you are trying to find the oxidation number of. The group number that it is in, equals the number of valence electrons that it has. Example, Chlorine is in group seven, so it has seven valence electrons. Since they want to be stable, and have eight valence electrons, it will do whatever it can to get that. So it just needs to gain one electron to have eight. Electrons are negative. So it is Cl-1. If you had one on the other end of the Periodic Table, it would want to lose electrons, making it negative.

Answer 6

The algebraic sum of the oxidation numbers is equal to the charge of the ion. Some of the atoms in the ion have known oxidation numbers and you use these to calsulate the ox, number of the unknown atom.

EX: Find the ox. state of S in SO3-2 Sulfur, the unknown, is x. Oxygen is almost always -2. write a little equation....

x + 3(-2) = -2 ..... now solve for x

x - 6 = -2

x = +4

Answer 7

It tells you the number of electrons gained or lost in an atom.

Answer 8

The oxidation number is the number of valence electrons. The valence electrons are the electrons on the outermost energy level.

Answer 9

This is the sum of of the oxidation states for the elements contained in the molecule.