![electron affinity chart electron affinity chart](http://hyperphysics.phy-astr.gsu.edu/hbase/Chemical/imgche/electronegnum.png)
We define the first electron affinity as the energy released when 1 mole of gaseous electrons are added to 1 mole of the element to form 1 mole of gaseous negative ions. In this case, it is important to differentiate between the addition of the first electron versus the second, as these have different electron affinity values. But some elements can form anions with a -2 charge. Typically, we are concerned with the addition of a single electron to an element (the first electron affinity). In other words, it is easier for non metals to gain electrons to form a noble gas configuration Nonmetals, on the other hand, are further right on the periodic table - meaning they are more likely to gain electrons to complete their outermost shell. This is because metals have fewer protons and a low nuclear charge, meaning that they do not easily attract negatively charged electrons. In general, metals have a low electron affinity, as they prefer to lose electrons. Some elements prefer to gain electrons, and some prefer to lose electrons - this depends on their electronic configuration and chemical properties. The electron affinity is related to the element’s position on the periodic table. Usually, by convention, as the energy is released, their values are written with negative signs. You may see these values with a positive sign or negative sign depending on the textbook or context. Both of these concepts, however, rely on the principles of nuclear charge and the ability to attract electrons.Įvery element has a different electron affinity. Electronegativity is the measure of how much an atom will attract a pair of electrons in a bond. Electron affinity is related to electronegativity, but is a quantitative measure of the energy change (in kilojoules per mole) of an atom when an electron is added. Electron affinity is the opposite of ionization energy (ionization energy is the energy required to remove an electron from an atom). This property is measured when the elements are in a gaseous state only - this is because it is measured with the atoms sufficiently separated so as to not have their energy levels be affected by surrounding atoms.
![electron affinity chart electron affinity chart](https://i.ytimg.com/vi/O2K0YjVlxs8/hqdefault.jpg)
Both of these concepts, however, rely on the principles of nuclear charge and the ability to attract electrons.Įlectron affinity is the measure of the energy released when an electron is added to an atom to create a negative ion. Is electron affinity the same as electronegativity? Of the metals, mercury has the lowest electron affinity.ģ. Metals are more likely to lose electrons than they are to gain them. Thus, the top right elements (except for the noble gases) have the highest electron affinities - the greatest energy released when an electron is added. Where is electron affinity highest on the periodic table?Įlectron affinity increases towards the top of the periodic table and towards the right. If an element gains an electron, this creates a negatively charged atom called an anion.ġ. In every element, an equal number of negatively charged electrons are present in shells surrounding the nucleus. Refresher: Elements have positively charged protons in their nucleus that give them a particular nuclear charge.