SO2 + CaO → CaSO3
This is an acid-base reaction (neutralization): SO2 is an acid, CaO is a base.
- SO2 – Sulfur dioxide
- Other names: Sulfurous anhydride , Sulphur dioxide , Sulfurous acid anhydride
- Appearance: Colorless gas ; Colourless gas or compressed liquefied gas with pungent odour ; Colorless gas with a characteristic, irritating, pungent odor. [Note: A liquid below 14°F. Shipped as a liquefied compressed gas.]
- CaO – Calcium oxide