the ability of an atom to attract electron towards itself is called electronegativity.
the ability of an atom to attract electron towards itself is called electronegativity.
the ability of an atom to attract electron towards itself is called?
electronegativity
electronegativity is a chemical property that describes the tendency of an atom or a functional group to attract electrons (or electron density) towards itself. if the bond between sodium and chlorine in sodium chloride were covalent, the pair of shared electrons would be attracted to the chlorine because the effective nuclear charge on the outer electrons is +7 in chlorine but is only +1 in sodium. the electron pair is attracted so close to the chlorine atom that they are practically transferred to the chlorine atom (an ionic bond). however, if the sodium atom was replaced by a lithium atom, the electrons will not be attracted as close to the chlorine atom as before because the lithium atom is smaller, making the electron pair more strongly attracted to the closer effective nuclear charge from lithium. hence, the larger alkali metal atoms (further down the group) will be less electronegative as the bonding pair is less strongly attracted towards them. as mentioned previously, francium is expected to be an exception.
alkali metal
the electron affinity of an atom can be described either as the energy released by an atom when an electron is added to it, conversely as the energy required to detach an electron from a singly charged anion. the sign of the electron affinity can be quite confusing, as atoms that become more stable with the addition of an electron (and so are considered to have a higher electron affinity) show a decrease in potential energy; i.e. the energy gained by the atom appears to be negative. for atoms that become less stable upon gaining an electron, potential energy increases, which implies that the atom gains energy. in such a case, the atom's electron affinity value is positive. consequently, atoms with a more negative electron affinity value are considered to have a higher electron affinity (they are more receptive to gaining electrons), and vice versa. however, in the reverse scenario where electron affinity is defined as the energy required to detach an electron from an anion, the energy value obtained will be of the same magnitude but have the opposite sign. this is because those atoms with a high electron affinity are less inclined to give up an electron, and so take more energy to remove the electron from the atom. in this case, the atom with the more positive energy value has the higher electron affinity. as one progresses from left to right across a period, the electron affinity will increase.
periodic trends