Illustrate born-haber cycle, Chemistry

Assignment Help:

Q. Illustrate Born-Haber cycle?

Boron is always covalent and does not   form,B3+ ions, because' the energy required to remove three electrons is very high.  Many simple compounds of A1 and Ga like AlCl3 and GaCl3 are also covalent when anhydrous. However, in solution, the large amount of hydration energy evolved compensates the high ionisation energy and all the' metal ions exist in a hydrated state.

This can be explained with the help of Born-Haber cycle as given below. However, this is a simplified approach given only on the bas; of enthalpy changes, whereas the direction and extent of any reaction depend on the free energy changes which take into account changes both in enthalpy and entropy.

365_Illustrate Born-Haber cycle.png

Thus, despite the large ionisation energies of aluminium, the enthalpy of' solution of  AlCl3 has a large negative value. Therefore, in aqueous solution, AIC3 exists as AI3+(aq) and Cl-(aq). It might be thought that the same argument would apply to BCI3; But to make the enthalpy of solution of BCl3 nethalpy the enthalpy of hydration of B3+ should be - 6009 KJ which is unlikely for the small B3+cation. Therefore, BC13 hydrolyses in aqueous solution to give boric acid and not B3+ (aq).

BCl3 + 3H20 -----------------------------------> H3B03 + 3HCI


Related Discussions:- Illustrate born-haber cycle

Properties, what are the physical properties of acetic acid?

what are the physical properties of acetic acid?

State about the point imperfection, State about the Point imperfection ...

State about the Point imperfection They are imperfect point-like regions in the crystal. One or two atomic diameters is the typical size of a point imperfection.  A substitu

Aavart sarini, aavart sarini ke liye koi trick hai kya?

aavart sarini ke liye koi trick hai kya?

Energy, The amount of energy released by burning a fuel source, measured in...

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.20 pounds of butane (fuel v

Redox Titration, What is the reliablitiy of redox titrations?

What is the reliablitiy of redox titrations?

Describe about groups or families in periodic table, Q. Describe about grou...

Q. Describe about groups or families in periodic table? Every element may be represented by a one or two letter symbol. In the middle of nineteenth century a Russian chemist Dm

Indicator, what is theory of indicators?

what is theory of indicators?

Can you describe cream foams, Q. Can you describe Cream Foams? Cream, w...

Q. Can you describe Cream Foams? Cream, with a fat content of at least 30 per cent, can be beaten to form foam. However, it is observed that a cream with 36 per cent fat can be

MOT, why Px orbitol reside outside in bonding orbitol in elements have Z>7

why Px orbitol reside outside in bonding orbitol in elements have Z>7

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd