Solubility of fluorides

  • #1
7
0

Homework Statement


The fluoride which is most soluble in water is:
a)CaF2
b)BaF2
c)SrF2
d)BeF2

Homework Equations


none

The Attempt at a Solution


the answer given is D.
but BeF2 is covalent in nature and is soluble in organic solvents.
Due to more electropositivity of Ba, BaF2 will have more ionic nature. On the other hand, since F is smaller compared to Ba, according to Fajan's rule, it can easily polarize Ba and it will have more covalent nature.
So i am confused about option C.
 

Answers and Replies

  • #2
James Pelezo
Gold Member
190
58
Beryllium Fluoride's water solubility in most MSDS documents is defined as highly soluble in water with no specific saturation values given. The other compounds in the answer choice list all have published Solubility Product Constants (Ksp-values) ranging from 10-7 to 10-9. This, of course, is 'elimination logic' based on the low solubility of the the first three choices, BeF2 is the only option remaining without a published Ksp value. .
 
  • #3
217
18
[My thinking] Since Be and F both are small in size , their hydration enthalpies should be high. Therefore the solubility of this compound should be considerable.
And for the others we should see the point of view of the electron robber flourine. The bigger cations can easily give their electrons as their ionisation energies are low...so why would flourine leave them to go free in water?
It has what it wants....electrons.
 

Related Threads on Solubility of fluorides

Replies
10
Views
36K
  • Last Post
Replies
5
Views
4K
Replies
4
Views
4K
  • Last Post
Replies
6
Views
817
Replies
3
Views
3K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
1
Views
12K
  • Last Post
Replies
5
Views
21K
  • Last Post
Replies
14
Views
2K
  • Last Post
Replies
1
Views
4K
Top