Which chemical properties below are those of the alkaline-earth metals?Form ions with a +1 chargeReadily oxidized to an oxidation state of +2Increasing reactivity with increasing atomic numberDecreasing reactivity with increasing atomic numberSoft Group 1 metals that form basic hydroxides in waterGroup 2 metals that form hydrogen gas when reacting with water

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11ecba2d_123d_d789_a3bf_a1c528e26feb_MD0008_00 The alkaline-earth metals are a highly reactive family of metals occupying Group 2 of the periodic table. Because the alkaline-earth metals have a low electronegativity and possess only two valence electrons, these metals have a low first and second ionization energy. As a result, the alkaline-earth metals readily lose both valence electrons (oxidize), which results in an oxidation state of +2 (Number II). As the atoms in the alkaline-earth metal group increase in size moving down the column, the valence electrons occupy an increasingly higher energy level and therefore are less tightly bound. Accordingly, less energy is required to remove the electrons from the valence shell of larger alkaline-earth metals. Consequently, the reactivity of the alkaline-earth metals increases with increasing atomic number (Number III). When reacting with water, the alkaline-earth metals of Group 2 form either a metal oxide or a very basic metal hydroxide solution while releasing hydrogen gas in the process (Number VI). (Number I) Forming ions with a +1 charge is a property of the alkali metals (Group 1) rather than the alkaline-earth metals (Group 2). (Number IV) Both alkali metals and alkaline-earth metals show an increase, not a decrease, in reactivity with increasing atomic number. (Number V) Although both alkali metals and alkaline-earth metals (except beryllium) form basic hydroxides in water, the alkaline-earth metals are in Group 2 rather than Group 1. Educational objective: Group 2 of the periodic table contains the alkaline-earth metals, which are a highly reactive family of metals with only two valence electrons that are readily lost to form cations with an oxidation state of +2. Alkaline-earth metals react with water to form hydrogen gas and either a basic hydroxide or an oxide, and the reactivity increases with increasing atomic number.

Which Chemical Properties Below Are Those of the Alkaline-Earth Metals?Form