Atomic disguise makes helium look like hydrogen
Atomic disguise makes helium look like hydrogen - physics-math - 28 January 2011 - New Scientist
18:37 28 January 2011 by Kate McAlpine
In a feat of modern-day alchemy, atom tinkerers have fooled hydrogen atoms into accepting a helium atom as one of their own. The camouflaged atom behaves chemically like hydrogen, but has four times the mass of normal hydrogen, allowing predictions for how atomic mass affects reaction rates to be put to the test.