Born haber cycle

Question 1

what is the born haber cycle?

Answer 1

a special type of hess cycle that represents the formation of an ionic compound

Question 2

endo

Answer 2

arrow is up

Question 3

exo

Answer 3

arrow is down

Question 4

What are the 5 features of a born haber cycle

Answer 4

1. enthalpy of formation AHF
2. atomisation of the non metal and metal AHat - TURN INTO GASEOUS ATOMS
3. ionization of the metal AHi Na+ + Cl- + e-
4. Electron affinity of the non metal AHea (negative ion) Na+ and Cl-
5. Lattice enthalpy of formation AHI
   NaCl

Question 5

What two factors affect lattice formation enthalpy

Answer 5

1. charge

2. size

Question 6

what is the perfect ionic model of a lattice - theoretical

Answer 6

it assumes that all the ions are spherical and has a even distribution of electron

Question 7

Experimental enthalpy

Answer 7

shows that ionic compounds have some covalent character

Question 8

why aren’t positive and negative ions always spherical

Answer 8

Positive ions polarize neighbouring negative ions to different extents – Partial covalent bonding =the electrons in the negative ion are pulled towards the positive ion.

Question 9

if the experimental and theoretical enthalpies are different….

Answer 9

the compound has a lot of covalent characters

Question 10

if the experimental and theoretical enthalpies are similar

Answer 10

the compound has very little of covalent characters