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oxidation numbers

im a bit confused here-

what would be the oxidations numbers in Mg(NO3)2

Mg is always 2+

NO3 therefore must be -1 (as there are two of them) - Oxygen needs two bonds so O is -2, Nitrogen must be 5+ as a result 3(-2) + 5 = -1 = charge on the anion

:smile:

Reply 2

zee11

so wait- oxygen would be -2 but would it be -2 x 6?

Reply 3

EierVonSatan

there are two NO3's, but I'm just talking about in each NO3

Reply 4

zee11

yh.. so just tell me is oxygen -12

Reply 5

EierVonSatan

no, oxygens oxidation state is -2 (of which there are 6 oxygen atoms)

Reply 6

zee11

yeah the state is -2 but when ur adding them all up it should be -12 right?

Reply 7

EierVonSatan

you don't add up oxidation states like this, no

oxygen's oxidation state in Mg(NO3)2 is -2 :smile:

Reply 8

AVAINTEX

Short Explanation on how you can Solve any Oxidation number problems.

From the periodic table there are facts all chemists and student must know

1- The oxidation number of alkali metals(Li,Na ,K ...) (Group 1A) is 1 and there is exceptions for hydrogen.

2- The oxidation number of Alkaline earth metals (Be,Mg...)(group 2A) is 2.

3- The transition metals have several Oxidation number.

4- Oxidation no of Al in group 3A is 3

5- Carbon in 4A is -4

6-The the Oxidation number decrease in group 5A N-3 also P-3

7-In 6A the Oxidation number of O,S,Se,Te is -2 there is exceptions also for Oxygen.

8-and finally in 7A (Halogens) The oxidation number is -1

Certain Names and formulas :yep:

of some organic and inorganic cation and anions You Need to memorize -Whispers- im going to give you the Important ones.

1-ammonium (NH4+)

2-nitrate (NO3-)

3-nitrite (NO2-)

4-(SO4-2)