Notes

Slag …

Slag – Glass like compound duced during the extraction of metals (smelting and refining) when the impurities in an ore react with a flux. For example, in blast furnance the flux used is limestone (CaCO3) and the main impurity silica (SiO2). The slag formed in mainly calcium silicate :
CaCO3 + SiOCaSiO3 + CO2.