I have the highest regard for Victoria Coren Mitchell, but I think she's wrong about "sulfur".
Most British people's aversion to "sulfur" is based on a suspicion that it's an Americanism, a consequence of the misguided spelling rationalisation that gave us "ax" and "color". In fact, many European languages use "f" in their various spellings (e.g. Schwefel, soufre, zolfo). I believe the "ph" in the English spelling was actually introduced as part of the curious Renaissance fashion for making words "more classical", the same trend that added the pointless "b" in "debtor".
"sulfur" is, of course, the spelling mandated by whatever international body controls the names of elements.