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Usingmolecular dynamics simulations, we study the hydrophobiceffect on electrically doped single layer graphene. With doping levelsmeasured in volts, large changes in contact angle occur for modestvoltages applied to the sheet. The effect can be understood as a renormalizationof the surface tension between graphene and water in the presenceof an electric field generated by the dopant charge, an entirely collectiveeffect termed electrowetting. Because the electronic density of statesscales linearly in the vicinity of the Fermi energy, the cosine ofthe contact angle scales quartically with the applied voltage ratherthan quadratically, as it would for a two-dimensional metal or inmultiple layer graphene. While electrowetting explains the phenomenon,it does not account for the slight asymmetry observed in the hydrophobicresponse between n- and p-doping. [ABSTRACT FROM AUTHOR]