Platinum is a silvery white metal and is highly unreactive then why it's powdered form "platinum black" is platinum metal but is black in colour. why would a metal such as platinum become black as a powder?

  • $\begingroup$ Might be related to light scattering from small particles of platinum (platinum black is a fine powder) vs. bulk, but not sure. Good question! $\endgroup$
    – Todd Minehardt
    Feb 11 '16 at 17:19
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    $\begingroup$ @ToddMinehardt is right, it's not about the chemistry, it's about the physics of how light interacts with it. As good as a question as it is, I'm flagging it as off-topic for Chem.SE, as it more properly belongs on Physics.SE. $\endgroup$
    – hBy2Py
    Feb 11 '16 at 17:27
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    $\begingroup$ @ToddMinehardt For reference, this answer on Physics.SE has a short paragraph about a related modification of $\ce{Pt}$ that also leads to a black color. $\endgroup$
    – hBy2Py
    Feb 11 '16 at 17:41
  • $\begingroup$ I wrote a relevant answer in a past question. $\endgroup$ Feb 12 '16 at 8:38
  • $\begingroup$ While the answer might be that's it's a physical effect rather than a chemical one, the question is still about a particular compound and the user wouldn't have known that it was a physical effect or else they wouldn't have asked here, so I'm glad the hold was removed. $\endgroup$
    – Tyberius
    Mar 27 '19 at 14:05