HCN + HF Reaction & Acid-Base Indicator Characteristics

[BayernBlues]

Hcn + Hf --> ?

Homework Statement

-What do HCN + HF form? (I've googled the reaction, can't find anything).
-Also, what're 3 good characteristics of an acid-base indicator?

Homework Equations

The Attempt at a Solution

I know it's an acid-base reaction. I'm guessin something like
HCN + HF --> NH3 + CF

-One good characteristic of an acid base indicator would be an intense colour change?

 

[chemisttree]

HCN has localized electrons available on the nitrogen and the proton (on carbon) is fairly acidic. This suggests that it should hydrogen bond fairly easily... but is the hydrogen in HF that available for hydrogen bonding?
Fluorine has a strong affinity for hydrogen... but is it strong enough to deprotonate the hydrocyanic acid?

 

[BayernBlues]

so I'm guessing then that there isn't a reaction? because judging from what you said, the only thing I can think of is:

HCN + HF ------> HCF3 + NH3