A carbonate is a salt of carbonic acid, H2CO3, characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO2−3. The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate group O=C(−O−)2.
Stalactites and stalagmites are carbonate minerals.
In chemistry, a salt or ionic compound is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a neutral compound with no net electric charge. The constituent ions are held together by electrostatic forces termed ionic bonds.
X-ray spectrometer developed by W. H. Bragg
Halite, the mineral form of sodium chloride, forms when salty water evaporates leaving the ions behind.
Solid lead(II) sulfate (PbSO4)
Edge-on view of portion of crystal structure of hexamethyleneTTF/TCNQ charge transfer salt.