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A condition called the zinc shakes or "zinc chills" can be induced by inhalation of zinc fumes while brazing or welding galvanized materials. [149] Zinc is a common ingredient of denture cream which may contain between 17 and 38 mg of zinc per gram. Disability and even deaths from excessive use of these products have been claimed. [246]
The oldest known pills were made of the zinc carbonates hydrozincite (described 1853) and smithsonite (described 1832). Calamine is a historic name for an ore of zinc (hemimorphite (IMA1962 s.p.) and smithsonite). [6] De architectura (about 15 BC) of Marcus Vitruvius Pollio, Libri X, vol. VII, Caput 8.
Lavoisier writes the first modern list of chemical elements – containing 33 elements including light and heat but omitting Na, K (he was unsure of whether soda and potash without carbonic acid, i.e. Na 2 O and K 2 O, are simple substances or compounds like NH 3), [91] Sr, Te; some elements were listed in the table as unextracted "radicals ...
The balangay was the first wooden marine vessel ever excavated in Southeast Asia. It is also known as the Butuan boat, as nine specimens of these boats, dating back to pre-Hispanic times (the earliest being in 320 CE), were discovered in 1976, Butuan, Mindanao. It is believed that the Austronesians migrated to the Philippine archipelago, riding ...
Sphalerite is an important ore of zinc; around 95% of all primary zinc is extracted from sphalerite ore. [42] However, due to its variable trace element content, sphalerite is also an important source of several other metals such as cadmium, [ 43 ] gallium, [ 44 ] germanium, [ 45 ] and indium [ 46 ] which replace zinc.
Anacleto del Rosario y Sales (July 13, 1860, Santa Cruz, Manila – May 2, 1895) was a leading chemist in the Philippines during the Spanish era in Philippine history. Regarded as the "Father of Philippine Science and Laboratory", del Rosario invented the formula for producing a pure kind of alcohol from tuba in a nipa palm.
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
The first shows the entire time from the formation of the Earth to the present, but this gives little space for the most recent eon. The second timeline shows an expanded view of the most recent eon. In a similar way, the most recent era is expanded in the third timeline, the most recent period is expanded in the fourth timeline, and the most ...