Electronegative

Atoms that are weakly electronegative (such as alkali metals ) have relatively few valence electrons that can easily be shared with atoms that are strongly electronegative.

Hence, fluorine is the most electronegative of the elements (not counting noble gases ), whereas caesium is the least electronegative, at least of those elements for which substantial data is available.

Lithium is the most electronegative of all the metals, with a standard electrode potential of 3 045 volts, meaning it can generate the greatest power per unit mass compared to other metals.

Almost all known xenon compounds contain the electronegative atoms fluorine or oxygen.

An image of a computed electrostatic surface of neutral phenol, showing neutral regions in green, electronegative areas in orange-red, and the electropositive phenolic proton in blue.

Carbides Carbides are binary compounds of carbon with an element that is less electronegative than it.

For example, in ammonium ion ( NHmain ) the oxidation state of nitrogen is −3, as all eight valence electrons are assigned to the nitrogen atom that is more electronegative than hydrogen.

In a hydrogen bond, the electronegative atom not covalently attached to the hydrogen is named proton acceptor, whereas the one covalently bound to the hydrogen is named the proton donor.

In reality, the atoms carry fractional charges ; the more electronegative atom of the two involved in the bond will usually carry a fractional negative charge.

In this case, the carbon atom carries the fractional negative charge despite its being less electronegative than oxygen.

It is also necessary to decide which of the two elements is the more electronegative (equivalent to choosing one of the two possible signs for the square root).

It is calculated by counting all the bonding electrons as belonging to the more electronegative oxygen.

Oxygen is more electronegative than carbon, thus the hydrogens alpha to ethers are more acidic than in simple hydrocarbons.

The other two bonding orbitals are each occupied by one electron from carbon and one from oxygen, forming (polar) covalent bonds with a reverse C → O polarization, since oxygen is more electronegative than carbon.

These covalent features are more substantial when acceptors bind hydrogens from more electronegative donors.

This is usually done using "chemical intuition": in the above example, hydrogen bromide dissolves in water to form H + and Br − ions, so it may be assumed that bromine is more electronegative than hydrogen.