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Boron exist in different allotropic form...

Boron exist in different allotropic forms. All allotropic form contains icosahedral units (icosahedral is regular shape with 12 corner & 20 faces) with boron atoms at all 12 corners and all bonds are equivalent.

Calculate heat evolved at constant pressure (in KJ) per mole of boron atoms undergoing above change it `DeltaH_(BE)(B-B) =200 KJ//"mol"`. Report you answer after dividing by 100

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The correct Answer is:
5
Heat evolved per mol of 'B' atoms `=(5)/(2)xx 200=500 KJ`
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One of the allotropic form of boron is alpha - rhombohedral boron. Number of faces and corners in its basic building B_(12) icosahedral unit are:

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The dipole moment of HBr is 2.6 xx 10^(-30)Cm and interatomic spacing is 1.41 A What is the percent ionic character of HBr (b) A diatomic molecule has mu = 1.2 D Its bond distance is 1.0A What fraction of electronic charge exists on each atom? (c ) In water, (H -O_H) bond angle is 105^(@) The distance between (O-H) is 0.94A.mu of H_(2)O=1.85D Determine the magnitude of the charge on the oxygen atom in water molecule and hydrogen atom (d) BI_(3) is a symmetrical planar molecule, all the (B -1) bonds lie at 120^(@) of each other. The distance between the I atoms is 3.54 A the radius of covalently bonded I atom is 1.33A Estimate the covalent radius of boron (e) Calculate the dipole moment of the following compounds .

RESONANCE-THERMODYNAMICS-exercise-3 part-2 Advanced level Solutions
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  5. Which of the following statement(s) is/are false?

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  7. Select the correct enthalpy at corresponding temperature using followi...

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  8. Two moles of a perfect gas undergo the following processes: (a) a re...

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  9. The enthalpy of combustion of mol. Wt. 180 glucose is -2808 KJ "mol"^(...

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  10. A sample of certain mas s of an ideal polyatomic gas is expanded agai...

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  11. The heat of combustion of acetylene is 312 Kcal . If heat of formatio...

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  13. 1 mole of an ideal gas is allowed to expand isothermally at 27^(@)C ti...

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  14. Concerete is produced from a mixture of cement , water, sand and small...

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  15. Concerete is produced from a mixture of cement , water, sand and small...

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  16. Concerete is produced from a mixture of cement , water, sand and small...

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  17. The accompanying diagram represents a reversible cannot cycle for an i...

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  18. The accompanying diagram represents a reversible cannot cycle for an i...

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  19. The accompanying diagram represents a reversible cannot cycle for an i...

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  20. Match column-I to column-II standard entropy in KJ/k-molar at 25^(@)C ...

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