Which of the following involves combination of two elements? Mark as favorite Copy Link NH3(g) + HCl(g) -> NH4Cl(s) 2SO2(g) + O2(g) -> 2SO3f(g) CaO(s) + CO2(g) -> CaCO3(g) N2(g) + 3H2(g) -> 2NH3(g) Check Answer