thiophosphoryl fluoride
... that thiophosphoryl fluoride ignites spontaneously in air, but burns too cold to hurt anyone?
... that <b id="mwDEg"><a href="./Thiophosphoryl_fluoride" id="mwDEk" rel="mw:WikiLink" title="Thiophosphoryl fluoride">thiophosphoryl fluoride</a></b> ignites spontaneously in air, but <a href="./Cool_flame" id="mwDEo" rel="mw:WikiLink" title="Cool flame">burns too cold</a> to hurt anyone?