Why are silver halides insoluble in nitric acid

The silver halides $\ce{AgCl},~\ce{AgBr},~\ce{AgI}$ are insoluble in $\ce{HNO3}$. This is given in J.D.Lee's inorganic chemistry text. (The strength of nitric acid is not specified though).

But won't this reaction take place? $$\ce{X- + HNO3 -> X2}$$

This example is taken from JD Lee's book itself: $$\ce{6Br- + 8HNO3 -> 3Br2 + 2NO + 6NO3- + 4H2O}$$

because concentrated Nitric acid is a powerful oxidizing agent.

• What kind of reaction is that ? It's not balanced either in elements or in charges. Mar 21 '16 at 16:48
• @Hippalectryon its a basic oxidation reaction. Mar 21 '16 at 16:53

Effectively, silver halides will not dissolve in water (they have incredibly low $K_\text{sp}$), so the reaction indicated is moot.... there is no appreciable concentration of bromide in solution to be oxidized.
$K_\text{sp}(\ce{AgBr}) = 5.0\times10^{-13} \Rightarrow [\ce{Br-}] \approx 700~\text{nM}$