# Hydrogen Halides' Trouble

There are some acids which are called the hydrogen halides.

They are $HCl , HF, HI, HBr$

I just want to know which one is the strongest among them and which one is the weakest in water?

Also which is the strongest and weakest acid or will they even be acids when not in aqueous solution ?

NOTE: I've thought of a reason but don't know if its valid or not. Its like the increasing atomic size from fluorine to iodine will be the cause of decrease in their bond energy with hydrogen and therefore $HI$ will dissociate most readily and hence will be the strongest.

Note by Rishabh Tripathi
5 years, 1 month ago

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Yep, your reasoning is perfectly correct.. HI having the weakest bond is the strongest of the given acids.. $\ddot \smile$

- 5 years, 1 month ago

I was having one more question in mind i.e. I know that increasing atomic size decreases bond energy but is there an explainable reason behind this or it is observed experimentally?

- 5 years, 1 month ago

Well I suggest you to refer this and read a bit more on bond dissociation energy.

- 5 years, 1 month ago