Rank the following in order of decreasing acid strength in aqueous solution: HCl, HOCl, HOBr,HOI.
A) HCl > HClO > HBrO > HIO
B) HIO > HBrO > HClO > HCl
C) HCl > HIO > HBrO > HClO
D) HClO > HCl > HBrO > HIO
E) HClO > HBrO > HCl > HIO

Respuesta :

Answer:

A) HCl > HClO > HBrO > HIO

Explanation:

The strength of an acid is related to the acid dissociation constant (Ka). This is the equilibrium constant for an acid. The higher the Ka, the stronger the acid.

An easier way to compare the strength of acids is through their pKa, where

pKa = -log Ka

The lower the pKa, the stronger the acid.

Let's consider the following acids and their pKa values:

HCl      -7

HClO   7.54

HBrO   8.62

HIO      10.64

The order of decreasing acid strength is:

A) HCl > HClO > HBrO > HIO