Oxidation Numbers

In aluminum oxide (Al₂O₃), the oxidation number of aluminum (Al) is +3, while the oxidation number of oxygen (O) is -2. Since there are two aluminum atoms contributing a total of +6 and three oxygen atoms contributing a total of -6, the compound is electrically neutral, confirming these oxidation states. Thus, the oxidation numbers are +3 for Al and -2 for O.

Zero(0) for elemental nitrogen.

However, nitrogen exhibits various oxidation numbers when combined with other elements, to form compounds.

The oxidation number is the number of electrons in the valence shell directly involved in the combination with another element.

e.g.

N2O = Oxid'n No. 1 (Nitrous oxide ' Laughing Gas').

NO = Oxidation No. 2 (Nitrogen monoxide)

NO2 = Oxid'n No. 4 (Nitrogen dioxide)

HNO3 = Oxidation No. 5 . (Nitric Acid)

HNO2 = Oxid'n No. 3 ( Nitrous Acid).

NB THere may be electrons in the valence shell not directly combining in a compound/reaction, known as 'lone pairs'.

NB

Phosphorus, which is in the same Group(V) as nitrogen also exhibits variable oxidation states.,

Elemental oxygen 'O2' is in zero oxidation state .

However, when oxygen is combined into moledcules, it is usually '-2' , but can be '-1'

NO!!!

Phosphates it is '+5'

Phosphides it is '-3'

+5

The phosphate anion is PO4^(3-) .

Using oxygen as the yardstick (standard ) at '-2'

The the four oxygens have an overall oxidation of 4 x -2 = -8

Then creating a sum

P - 8 = -3 ( The anionic chagre0.

P = -3 + 8

P = +5 .

NB In the nitrogen group , which includes phosphorus, the elements have variable oxidation states.

The oxidation number of Ca in CaO2 is +1. This is because the oxidation number of O is -2, and since there are two O atoms in CaO2, the overall charge contributed by the oxygen atoms is -4 (2*-2). Therefore, the oxidation number of Ca must be +1 to balance the charges and make the compound neutral.

There is no widely recognized convent or religious institution specifically known as "SN tANCO." It is possible that it could refer to a small, local community or a specific group not documented in mainstream sources. If you have more context or details, I can help further!

'3'

H3PO3

To calculate oxidation no. First sepatate out the ion.

In this case PO3^(3-).

Using oxygen as tha standard at '-2'.

Then the oxygen moiety is '3 X -2 = -6'

Creating a little sum

P + -6 = -3 (The charge on the ion) .

Add '6' t

NB 'P' is in the same group as 'N' . Elements in this Group have variable oxid'n numbers.

Hence

P -6 + 6 = -3 +6

P = +3 The oxidation number of 'P'.

In CsO2, cesium (Cs) has an oxidation number of +1 because alkali metals typically have an oxidation number of +1. Oxygen (O) typically has an oxidation number of -2 in compounds. Since the overall charge of CsO2 is neutral, the oxidation number of oxygen would be calculated as follows: (oxidation number of Cs) + 2(oxidation number of O) = 0. Therefore, the oxidation number of oxygen in CsO2 is -1.

The oxidation number of K in KOH is +1 because it is an alkali metal. Oxygen (O) typically has an oxidation number of -2 in compounds. Hydrogen (H) usually has an oxidation number of +1 in compounds. By applying these values, the oxidation number of KOH is -1.

In the tetrathionate ion (S4O6)2-, the total charge of the ion is 2-. Each oxygen atom has an oxidation number of -2, totaling -12 for all six oxygen atoms. Since the overall charge is 2-, the sum of the oxidation numbers of sulfur atoms must equal +2. With four sulfur atoms present, each sulfur atom in the tetrathionate ion has an oxidation number of +6.

The oxidation number for H in H4P2O7 is +1. Each hydrogen atom has an oxidation number of +1 because it is bonded to more electronegative elements like P and O, which have higher electronegativity values.

CN- group has an overall charge of -1. C has oxidation of +2 and N -3 in CN since N has more negativity than C. In other words, N competes and wins with C when both try to take electrons to satisfy their need to become stable. Cheers.

When calculating oxidation numbers, use '-2' (oxygen) as the 'yardstick'(standard).

Since SO3 has three oxygens, then the oxygen moiety is 3 x -2 = -6

Since SO3 is a neutrally charged molecule, overall oxidation is '0'.

Hence

S + -6 = 0

Hence S = 6 is the oxudation number for sulphur.

NB Sulphur exhibits different oxidation states in different molecules.

S = 0

SO2 = 4

SO3 = 6 ( as above)

H2SO4) = 6

H2S2O7 (Oleum) = 6

Elemental sulphur, like all other elements, has an oxidation number of zero(0).

However, when combined with other elements into molecules, it displays different oxidation number.s

H2S = -2

SO2 = +4

SO3 = +6

H2SO4 = + 6

HCN ( hydrogen cyanide) has the structurte H-C///N ( /// = triple bond).

The oxidation number of an atom is the number of outer most electrons used in forming a bond. Not all the outer most electrons are used, some can remain as 'lone pairs'.

Carbon ALWAYS has an oxidation no. of '+4' . It never varies. Hydrogen has an oxidaton number of '+1'. It is the nitrogen that has the variable oxidation. number.

HCN forms the ions , H^(+) & CN^(-)

Since carbon is always '4' and the overall charge of the ion is '-1' , then we can form a sum .

4 + N = -1

N = -1 -4

N = -5 is the oxid'n no/ of nitrogen in HCN. ( All five of nitrgens outer most electrons are involved in the bonding process. ). Compare with ammonia NH3 , Here nitrogen's oxid'n No. is '3' leaving a 'lone pair' of electrons not used in the outer most electron shell.

'4' .

Carbon atoms have four electrons in their outer energy shell. This leaves space to accept four more electrons to formvfour covalent bonds.

The oxidation number refers to the number of electrons in the outer energy shell that are used in combination with other atoms. Since carbon uses all four electrons , then its oxidation number is '4'.

Other elements, notably nitrogen have variable oxidation number.

Nitrgen when combined with hydrogen to form ammonia has an oxidation number of '3'. Because only three electrons out of the five electrons , in the outer energy shell, are used in combination with hydrogen.

In MnO2, the oxidation number of oxygen is typically -2. Since there are two oxygen atoms in MnO2, the total oxidation number contributed by oxygen is -4. The overall charge of the compound is neutral, so the oxidation number of manganese (Mn) can be calculated by setting the total oxidation number equal to zero. Therefore, the oxidation number of Mn in 2MnO2 is +4.

When calculating oxidation numbers, use '-2' for oxygen as a standard. It does vary in some oxygen molecules, but '-2' is a good starting point.

So in KNO3

The oxygen moiety is 3 x -2 = -6

Potassium(K) is always '+1' because it only loses one electron .

Hence the nitrgen os

+1 + N - 6 = 0

N- 5 = 0

N = +5 (oxidation state)

NB For neutrally charged molecule, the sum of the oxidation number is always 'zero'(0).

When calculating oxidation states of compounds containing PPh3 (triphenylphosphine), each phenyl group (Ph) is considered electrically neutral and contributes zero charge. Therefore, the charge of PPh3 is equal to the charge of the phosphorus atom in the compound. Phosphorus typically has an oxidation state of +3 in PPh3, making the overall charge of PPh3 neutral.

Well, honey, the oxidation number of strontium in the hydride of strontium is +2. It's like asking if Betty White is a national treasure - the answer is obviously yes. So, in this case, strontium is happily rocking that +2 oxidation number like a boss.

-1

In the compound NH3, hydrogen has an oxidation number of +1. This is because hydrogen typically has an oxidation number of +1 when bonded to nonmetals like nitrogen in ammonia. The sum of the oxidation numbers in a neutral compound is zero, so the nitrogen in NH3 has an oxidation number of -3 to balance the +1 oxidation number of each hydrogen atom.

Well, isn't that a happy little question! In Na3PO3, the oxidation number for Na is +1 and for O is -2. Since the overall charge of Na3PO3 is neutral, we can calculate the oxidation number for P to be +3. Just remember, there are no mistakes in oxidation numbers, only happy little accidents!

The answer is +7 because the oxygen has a charge of -8 and the charge on the whole compound is -1 therefore the charge on Cl must be +7.