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This list of chemical elements named after places includes elements named both directly and indirectly for places. 41 of the 118 chemical elements have names associated with, or specifically named for, places around the world or among astronomical objects.
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 ...
This list of chemical elements named after people includes elements named for people both directly and indirectly. Of the 118 elements, 19 are connected with the names of 20 people. 15 elements were named to honor 16 scientists (as curium honours both Marie and Pierre Curie). Four others have indirect connection to the names of non-scientists. [1]
Chlorosis occurs in younger leaves because iron is not a mobile element, and as such, the younger leaves cannot draw iron from other areas of the plant. Over time, the yellowing may even turn a pale white or the whole leaf may be affected. [4] Iron deficient plants may overaccumulate heavy metals such as cadmium. [5]
A space between the threads of a net, e.g. that part of a leaf surface defined by each of the elements of a vein network; as with cacti, the area between the veinlets of a leaf. 2. A structure on the stem node of a cactus , morphologically a specialised branch; the region of a cactus upon which spine s, glochid s, and flowers are borne.
Tantalum is a very hard, ductile, lustrous, blue-gray transition metal that is highly corrosion-resistant. It is part of the refractory metals group, which are widely used as components of strong high-melting-point alloys.
A common symptom of calcium deficiency in leaves is the curling of the leaf towards the veins or center of the leaf. Many times this can also have a blackened appearance. [ 40 ] The tips of the leaves may appear burned and cracking may occur in some calcium deficient crops if they experience a sudden increase in humidity. [ 18 ]
This element forms a large number of organogermanium compounds, such as tetraethylgermanium, useful in organometallic chemistry. Germanium is not thought to be an essential element for any living organism. Similar to silicon and aluminium, naturally-occurring germanium compounds tend to be insoluble in water and thus have little oral toxicity.