Heterogeneous microchemistry between CdSO4 and CaCO3 particles under humidity and liquid water

► Raman analysis of chemical reactions between CdSO4 and CaCO3 particles. ► Under humid air no changes of morphology and chemical composition were observed. ► Condensation of liquid water generates an insoluble CdCO3 layer on CaCO3 surface. ► Addition of water previously equilibrated with CaCO3 generates CdCO3 and CaSO4.