These are the rules of assigning oxidation numbers in compounds (in order of priority):
1. All group 1 metals have an ON of +1
2. Group 2 metals have an ON +2
3. Al is in group 3 and so has an ON of +3
4. O has an ON of -2 (except in peroxides where it is -1)
5. H has an ON of +1 (except in metal hydrides where it is -1)
6. F has an ON of -1
7. Cl has an ON of -1 except in compounds with O and F
Therefore, to assign C a oxidation number you have to work out the rest first as all the oxidation numbers in the compound have to make 0.
Mg has a ON of +2. (rule 2)
O has an ON of -2 (rule 4) but there are 3 O's and so you have to do 3x-2 = -6
Therefore, you have -6 (O) + 2 (Mg) = -4
Therefore, the ON of C must be +4 to make it equal to 0.
Oxidation numbers of the individual elements:
Mg C O3
+2 +4 -2
The oxidation number of carbon in magnesium carbonate is 4.
Magnesium and carbonate are divalent.
Barium Carbonate is BaCO3 and the oxidation numbers are +2 for barium, +4 for carbon and -2 for each oxygen.
+2
The oxidation number is + for C and -2 for O.
The answer is 9,3945.1023 molecules.
Magnesium and carbonate are divalent.
+4 for carbon
Carbonate is CO32- ion and the oxidation numbers are +4 for carbon and -2 for each oxygen.
I believe K2CO3.
Barium Carbonate is BaCO3 and the oxidation numbers are +2 for barium, +4 for carbon and -2 for each oxygen.
+2 for Mg, +4 for C, -2 for each O in MgCO3
Carbon has an oxidation number of +4 in both carbonate and bicarbonate. Oxygen as usual has an oxidation number of -2, and hydrogen has an oxidation number of +1. Therefore, the ion CO3-2 has six negative charges from oxygen partly balanced by four positive changes from carbon for a net of -2, and HCO3-1 has six negative charges from oxygen partly balanced by one positive from hydrogen and needs for plus four from carbon for an overall value of -1.
Magnesium is in the group 2. 0 is the lowest oxidation number for it.
Singl atom has 12 electrons. Oxidation number of it is +2.
In the carbonate CO32- the sum of the oxidation numbers is the ionic charge (true for all poyatomic ions) O is assigned -2 so C has +4. (maths 4 +(-6) = -2)
The oxidation number of magnesium is +2. Any other for this element would be energetically unfavorable and unstable.
Carbon has +2 oxidation number in Carbon monoxide. It gets this oxidation number when it loses or shares two electrons.