We have studied the surface chemistry of 6H-SiC(0001) and 6H-SiC (000 (1) over bar) after wet-chemical treatment using photoelectron spectroscopy (PES) and low-energy electron diffraction (LEED). The origin of chemically shifted components in the Si2p and C1s spectra is discussed in the light of previous studies on wet-chemically prepared surfaces and on silicate adlayer reconstructed surfaces. On 6H-SiC(0001) an ordered silicate adlayer was prepared by etching the surface with sulfuric acid based agents.