# Evidence in favour of WERNER’S THEORY

### 1. Electrical Conductance Measurement:

• Molar conductance of a substance depends upon the number of charges on the particle produced by the substance.
• As the number of the particle (i.e. ions) and charges on the coordination sphere increases, molar conductance of the compound increases.
• For example molar conductance for aqueous solution of cobalt(III)chloride complexes with ammonia decreases in the order,
[Co(NH3)6]Cl3 > [Co(NH3)5Cl]Cl2  > [Co(NH3)4Cl2]Cl  > [Co(NH3)3Cl3]
number of particle/ions       4                       3                      2                         1
charge      -3                      -2                    -1                         0

1.[Co(NH3)6]Cl3 →  [Co(NH3)6]3+ + 3Cl
2.[Co(NH3)5Cl]Cl2  → [Co(NH3)5Cl]2+ + 2Cl
3.[Co(NH3)4Cl2]Cl→ [Co(NH3)5Cl]++ Cl
4.[Co(NH3)3Cl3]

If we notice the 1st equation, it is clear that  [Co(NH3)6]Cldissociates to give 4 particles i.e.one  [Co(NH3)6]3+ ion and three Cl  ion And charge on the coordination sphere is -3.
So if we consider all the above equations, we will notice that there is a decreasing order in the number of particles and charges, on the coordination sphere from top to bottom. Therefore molar conductance decreases from top to bottom.

### 2.Cryoscopic Measurement:

• The cryoscopic measurement means, measurement of depression in freezing point.
• The depression in freezing point is a colligative property and depends upon the number of particles in the solution. Greater the number of particle more will be the depression in freezing point.
• If a species dissociates into two, three, four…….ions, then depression in freezing point will be two, three, four ……. times respectively.
• Thus the cryoscopic measurement gives the number of ions produced by the dissociation of an ionic compound.

### 3.Precipitation Reaction:

• The number of ions furnished by a coordination compound can also be determined by precipitation reactions.
• When the complexes CoCl3.6NH3,CoCl3.5NH3 ,CoCl3.4NH3 are treated with an excess of AgNO3 solution, the number of chloride ion precipitated as AgCl is 3, 2, 1 respectively. This indicates that the number of chloride ion in the ionization sphere is 3, 2, and 1 respectively. The reactions are given below,

CoCl3.6NH3 +3 AgNO3 → 3AgCl + [Co(NH3)6](NO3)3

CoCl3.5NH3 + 2AgNO3 → 2AgCl + [Co(NH3)5Cl](NO3)2

CoCl3.4NH3 + AgNO3 → AgCl + [Co(NH3)4Cl2](NO3)

• The structure provided by precipitation reactions is similar to those given by Werner.
• The complex gives no precipitate with the solution. This indicates that all three chloride ion is present in the coordination sphere in this compound.

## 9 thoughts on “Evidence in favour of WERNER’S THEORY”

1. It is a great post. Keep sharing such kind of useful information.

2. Thanks for your extraordinary blog. Your idea for this was so brilliant. This would provide people with an excellent tally resource from someone who has experienced such issues. You would be coming at the subject from a different angle and people would appreciate your honesty and frankness. Good luck for your next blog!
Tally ERP 9 Training
tally classes
Tally Training institute in Chennai
Tally course in Chennai
seo training classes
seo training course
seo training institute in chennai
seo training institutes
seo courses in chennai
seo institutes in chennai
seo classes in chennai
seo training center in chennai