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A strong base is a basic chemical compound that can remove a proton (H +) from (or deprotonate) a molecule of even a very weak acid (such as water) in an acid–base reaction. Common examples of strong bases include hydroxides of alkali metals and alkaline earth metals, like NaOH and Ca(OH) 2, respectively. Due to their low solubility, some ...
As usual, a weaker acid has a stronger conjugate base. Examples of Lewis bases based on the general definition of electron pair donor include: simple anions, such as H − and F −; other lone-pair-containing species, such as H 2 O, NH 3, HO −, and CH 3 −; complex anions, such as sulfate; electron-rich π-system Lewis bases, such as ethyne ...
Bases are defined by the Brønsted–Lowry theory as chemical substances that can accept a proton, i.e., a hydrogen ion. In water this is equivalent to a hydronium ion). The Lewis theory instead defines a Base as an electron-pair donor. The Lewis definition is broader — all Brønsted–Lowry bases are also Lewis bases.
2,6-Di-tert-butylpyridine, a weak non-nucleophilic base [2] pK a = 3.58; Phosphazene bases, such as t-Bu-P 4 [3] Non-nucleophilic bases of high strength are usually anions. For these species, the pK a s of the conjugate acids are around 35–40. Lithium diisopropylamide (LDA), pK a = 36
An organic base is an organic compound which acts as a base. Organic bases are usually, but not always, proton acceptors. They usually contain nitrogen atoms, which can easily be protonated. For example, amines or nitrogen-containing heterocyclic compounds have a lone pair of electrons on the nitrogen atom and can thus act as proton acceptors. [1]
In a vigesimal place system, twenty individual numerals (or digit symbols) are used, ten more than in the decimal system. One modern method of finding the extra needed symbols is to write ten as the letter A, or A 20, where the 20 means base 20, to write nineteen as J 20, and the numbers between with the corresponding letters of the alphabet.
An example of a weak base is ammonia. It does not contain hydroxide ions, but it reacts with water to produce ammonium ions and hydroxide ions. [4] The position of equilibrium varies from base to base when a weak base reacts with water. The further to the left it is, the weaker the base. [5]
It was a vigesimal (base-20) positional numeral system. The numerals are made up of three symbols: zero (a shell), [1] one (a dot) and five (a bar). For example, thirteen is written as three dots in a horizontal row above two horizontal bars; sometimes it is also written as three vertical dots to the left of two vertical bars.