Chemical test for heavy water

First of all, please refer to the physical properties between H2O and D2O (heavy water) as described in wikipedia.

Physical properties (with comparison to light water)
Property D2O (Heavy water) H2O (Light water)
Freezing point (°C) 3.82 0.0
Boiling point (°C) 101.4 100.0
Density (at 20°C, g/mL) 1.1056 0.9982
Temp. of maximum density (°C) 11.6 4.0
Viscosity (at 20°C, mPa·s) 1.25 1.005
Surface tension (at 25°C, μJ) 7.193 7.197
Heat of fusion (cal/mol) 1,515 1,436
Heat of vaporisation (cal/mol) 10,864 10,515
pH (at 25°C) 7.41 (sometimes "pD") 7.00

We can distinguish D2O by instrumental analysis, the most easilest and confirmed way is by nuclear magnetic resonance spectrometry and mass spectrometry.

However, if you insist to use chemical "reagent" and distinguish by observable change (by human eye), such like precipitate or color change, it is hardly possible.