Limestone is a widely and diversely used material.
Colourless, odourless, heavier-than-air gas. Necessary for the photosynthesis of plants.
Colourless, odourless gas, highly toxic to humans and animals in high concentration.
Colourless, odourless liquid produced by dissolving carbon dioxide in water.
An exercise about compound ions.
One of the oxoacids of nitrogen. A colourless compound with a pungent odour, a strong oxidant.
Potassium permanganate is used as a disinfectant.