Observed in Illinois on the first Monday of March every year, the holiday ostensibly honors Polish-born Revolutionary War cavalry officer Casimir Pulaski, though for most school kids with a four-day week, itâs probably just another sweet, sweet sleep-in day.
Yes, in chemistry a pure substance means either an element or a compound. Thus, hydrogen, oxygen, sodium, iron, copper etc. are pure substances; and so are compounds such as water, sugar, ammonia, sodium chloride, methane, ethanol etc. A compound is composed of two or more elements combined in a fixed ratio by mass. Like an element, a compound also has a distinct chemical identity. A mixture is not a pure substance as it is a collection of two or more elements/compounds in varying ratio. Air, sea water, gasoline, vegetable oils, steel etc. are mixtures.
Ammonia is the chemical name for the molecular formula NH3, which is a compound of nitrogen and hydrogen. It is also known by the name azane.... Ammonia is the chemical name for the molecular formula NH3, which is a compound of nitrogen and hydrogen. It is also known by the name azane. Ammonia has the properties of a colorless gas with a strong, characteristic odor. It has a density approximately half that of air and liquefies easily. Liquid ammonia is known by the name ammonium hydroxide. The odor of ammonia is easily neutralized with sodium bicarbonate. Ammonia is frequently used as an industrial fertilizer, a cleansing agent, a nitrogen source in the fermentation industry, and an effective antimicrobial agent in the food industry.