Editing Planetary core (section)

===Weight deficit components – Earth===

[[Sulfur]] is strongly siderophilic and only moderately volatile and depleted in the silicate earth; thus may account for 1.9 weight&nbsp;% of Earth's core.<ref name="Wood, Walter and Jonathan 2006" />  By similar arguments, [[phosphorus]] may be present up to 0.2 weight&nbsp;%. Hydrogen and carbon, however, are highly volatile and thus would have been lost during early accretion and therefore can only account for 0.1 to 0.2 weight&nbsp;% respectively.<ref name="Wood, Walter and Jonathan 2006" /> [[Silicon]] and [[oxygen]] thus make up the remaining mass deficit of Earth's core; though the abundances of each are still a matter of controversy revolving largely around the pressure and oxidation state of Earth's core during its formation.<ref name="Wood, Walter and Jonathan 2006" /> No geochemical evidence exists to include any radioactive elements in Earth's core.<ref name="McDonough 2003" />  Despite this, experimental evidence has found [[potassium]] to be strongly siderophilic at the temperatures associated with core formation, thus there is potential for potassium in planetary cores of planets, and therefore [[potassium-40]] as well.<ref name="Murthy, van Westrenen and Fei 2003">{{cite journal |last1=Murthy |first1=V. Rama |last2=van Westrenen |first2=Wim |last3=Fei |first3=Yingwei |title=Experimental evidence that potassium is a substantial radioactive heat source in planetary cores |journal=Letters to Nature |volume=423 |issue=6936 |date=2003 |pages=163–167 |doi=10.1038/nature01560|pmid=12736683 |bibcode = 2003Natur.423..163M |s2cid=4430068 }}</ref>