In each row, the box under the compound that can reasonably be expected to be more acidic in aqueous solution, e. g. have the larger ka.

h2 teo4 h2teo3
hclo2 hclo
hclo hbro

H2TeO3

HClO2

HClO

Explanation:

Ka is the value of the equilibrium constant of the acids. As higher is it's valued, as higher is the value of the concentration of H+, so more acidic is the solution. Another way to determine the acidic is to obtain the pKa = -logKa, in this case, as larger the pKa, as less acidic is the solution. The values of pKa can be found at analytic tables.

First row:

H2, pKa = 15.74

TeO4, pKa = 11

H2TeO3, pKa1 = 2.7

More acidic = H2TeO3

Second row:

HClO2, pKa = 1.94

HClO, pKa = 7.40

More acidic = HClO2

Third row:

HClO, pKa = 7.40

HBrO, pKa = 8.55

More acidic = HClO

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