# Predicting the Bond-Order of Oxides based Acid Radicals

Innovative study for the prediction of bond order in case of oxide based acid radicals have been discussed here1-3.

In case of oxide based acid radicals

Bond Order (B.O.) = Valency of the peripheral atom + (Charge on Acid Radical / Total number of peripheral atoms)

Eg.:

• ClO4- : (Valency of one Peripheral atom Oxygen = 2, Charge on acid radical = -1, Total Number of Peripheral atoms = 04), Therefore B.O. = 2 + (-1/4) = 1.75
• ClO3- : (Valency of one Peripheral atom Oxygen = 2, Charge on acid radical = -1, Total Number of Peripheral atoms = 03), Therefore B.O. = 2 + (-1/3) = 1.66
• ClO2- : (Valency of one Peripheral atom Oxygen = 2, Charge on acid radical = -1, Total Number of Peripheral atoms = 02), Therefore B.O. = 2 + (-1/2) = 1.5
• AsO43- : (Valency of one Peripheral atom Oxygen = 2, Charge on acid radical = -3, Total Number of Peripheral atoms = 04), Therefore B.O. = 2 + (-3/4) = 1.25
• AsO33-: (Valency of one Peripheral atom Oxygen = 2, Charge on acid radical = -3, Total Number of Peripheral atoms = 03), Therefore B.O. = 2 + (-3/3) = 1.0
• SO42- : (Valency of Peripheral atom Oxygen = 2, Charge on acid radical = -2, Number of Peripheral atoms = 04), Therefore B.O. = 2 + (-2/4) = 1.5
• SO32- : (Valency of Peripheral atom Oxygen = 2, Charge on acid radical = -2, Number of Peripheral atoms = 03), Therefore B.O. = 2 + (-2/3) = 1.33
• PO43- ; (Valency of Peripheral atom Oxygen = 2, Charge on acid radical = -3, Number of Peripheral atoms = 04), Therefore B.O. = 2 + (-3/4) = 1.25
• BO33- ; (Valency of Peripheral atom Oxygen = 2, Charge on acid radical = -3, Number of Peripheral atoms = 03), Therefore B.O. = 2 + (-3/3) = 1
• CO32- ;(Valency of Peripheral atom Oxygen = 2,Charge on acid radical = -2, Number of Peripheral atoms = 03), Therefore B.O. = 2 + (-2/3) = 1.33
• SiO44-:(Valency of Peripheral atom Oxygen = 2,Charge on acid radical = - 4, Number of Peripheral atoms = 04), Therefore B.O. = 2 + (- 4/4) = 1

## Relation (Bond order vs. Bond length, Bond Strength, Bond energy, Thermal stability and Reactivity)

B.O. α 1 / Bond length or Bond distance;

B.O. α Bond strength;

B.O. α Bond Energy;

B.O. α Thermal Stability; B.O. α 1 / Reactivity

### Correlation (Literature values of bond-distances of some oxide based acid radicals with their predicted bond order values)

Literature values of the Cl-O average bond lengths in ClO4-,ClO3- and ClO2- ; As-O bond lengths in AsO43- and AsO33- with respect to their bond order values suggest that with increasing bond-order M-O bond length (Where M = Cl, As etc.) decreases which is shown in Table-1.

Table 1:Bond-distances and their predicted bond order values

Bond-Order Values

Avg. M-O Bond-Distances

As per Literature (Å)

Remarks

ClO4-

1.75

1.50

Increasing Bond-Order decreases Bond Length

ClO3-

1.6

1.57

ClO2-

1.5

1.64

AsO43-

1.25

1.75

AsO33-

1.0

1.77

## References

1. Arijit Das,‘New Methods for Prediction of Bond Order of Mono and Diatomic Homo and Hetero Nuclear Molecules or Ions Having (1-20)e-s and Oxide Based Acid Radicals Without MOT – a Rapid Innovative Approach’,IJAR, 2013, 3(11), 41-43, ISSN-2249-555X.
2. Arijit Das, ‘Simple Thinking Makes Chemistry Metabolic And Interesting- A Review Article’, IOSR-JAC, 2013, 6(4), 8-15, e-ISSN: 2278-5736, doi:10.9790/5736-0640815.
3. Arijit Das, R.Sanjeev and V.Jagannadham, “Innovative And Time Economic Pedagogical Views In Chemical Education – A Review Article”, World Journal of Chemical Education, 2014, 2(3), 29-38, Science and Education Publishing , USA, DOI:10.12691/wjce-2-3-1.