Why ionization energy of alkali metals decrease down the group?

Down the group, the increase in nuclear charge is exactly offset by the increase in the number of inner electrons. However, the distance between the nucleus and the outer electrons increases down the group; electrons become easier to remove, and the ionization energy falls.

Does the ionization energy of alkali metals increase or decrease going down the group?

Group 1 elements are known as Alkali Metals. Progressing down group 1, the atomic radius increases due to the extra shell of electrons for each element. Going down the group, the first ionisation energy decreases.

Why ionization energy for the alkaline earth metals is higher than the ionization energy for the alkali metals?

Along the period from left to right, atomic number increaes and, therefore, nuclear charge also increases. So first ionization energies of alkaline earth metals are higher than those of the alkali metals of the same period because of higher nuclear charge.

Why do alkali metals and alkaline earth metals form cations?

As with the alkali metals of Group 1 (Ia), the atoms of the alkaline-earth metals easily lose electrons to become positive ions (cations). Most of their typical compounds are therefore ionic: salts in which the metal occurs as the cation M2+, where M represents any Group 2 atom.

How does ionization energy change down a group?

Ionization energy depends mainly on the strength of the attraction between the negative electron and the positive nucleus. When we move down a group in the periodic table, more energy levels are added, and so valence electrons would become further and further away from the positive nucleus.

How does ionisation energy vary down a group?

Variation of ionization energy down the group: On moving down the group, the ionization enthalpy decreases. This is because the electron is to be removed from the larger valence shell. As a result, the outer electron is held more tightly, and hence, the ionization enthalpy increases across a period.

How does ionization energy vary for the alkali metals?

Ionization energy increases from bottom to top within a group, and increases from left to right within a period. The trend within a group can be seen easily by observing how the ionization energies vary for either the alkali metals (Li through Cs) or the noble gases (He through Rn).

Do alkaline earth metals have low ionization energy?

The alkaline metals have the second-lowest first ionization energies in their respective periods of the periodic table. This is due to their low effective nuclear charges and the ability to attain a full outer shell configuration by losing just two electrons.

Which is more likely to have a higher ionization energy an alkaline earth metal or a halogen?

Halogens would be most likely to react with alkali metals, which contain only one loosely bound electron in the valence shell. Alkali metals have very low ionization energy, readily losing an electron, while halogens have very high electronegativity, readily gaining an electron.