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  2. Tin - Wikipedia

    en.wikipedia.org/wiki/Tin

    Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead, and has two main oxidation states, +2 and the slightly more stable +4. Tin is the 49th most abundant element on Earth, making up 0.00022% of its crust, and with 10 stable isotopes, it has the largest number of stable isotopes in the periodic table, due to ...

  3. Nucleophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_substitution

    In chemistry, a nucleophilic substitution (S N) is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile). The molecule that contains the electrophile and the leaving functional group is called the substrate.

  4. Silicon nitride - Wikipedia

    en.wikipedia.org/wiki/Silicon_nitride

    Silicon nitride is a chemical compound of the elements silicon and nitrogen. Si 3 N 4 (Trisilicon tetranitride) is the most thermodynamically stable and commercially important of the silicon nitrides, [6] and the term ″Silicon nitride″ commonly refers to this specific composition.

  5. List of chemical elements - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical_elements

    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 ...

  6. List of semiconductor materials - Wikipedia

    en.wikipedia.org/wiki/List_of_semiconductor...

    A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).

  7. SN2 reaction - Wikipedia

    en.wikipedia.org/wiki/SN2_reaction

    The bimolecular nucleophilic substitution (S N 2) is a type of reaction mechanism that is common in organic chemistry. In the S N 2 reaction, a strong nucleophile forms a new bond to an sp 3-hybridised carbon atom via a backside attack, all while the leaving group detaches from the reaction center in a concerted (i.e. simultaneous) fashion.

  8. SN1 reaction - Wikipedia

    en.wikipedia.org/wiki/SN1_reaction

    In inorganic chemistry, the S N 1 reaction is often known as the dissociative substitution. This dissociation pathway is well-described by the cis effect. A reaction mechanism was first introduced by Christopher Ingold et al. in 1940. [3] This reaction does not depend much on the strength of the nucleophile, unlike the S N 2 mechanism. This ...

  9. Isotopes of tin - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_tin

    Tin (50 Sn) is the element with the greatest number of stable isotopes (ten; three of them are potentially radioactive but have not been observed to decay). This is probably related to the fact that 50 is a "magic number" of protons.