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What is the acid-base properties

The main properties are exhibited by metals, their oxides andhydroxides. Acidic properties are manifested by nonmetals, their salts, acids and anhydrides. There are also amphoteric elements that can exhibit both acidic and basic properties. Zinc, aluminum and chromium are among the representatives of amphoteric elements. Alkaline and alkaline earth metals exhibit typical basic properties, and sulfur, chlorine and nitrogen are acidic. Thus, when oxides react with water, depending on the properties of the base element, either a base or a hydroxide or an acid is obtained. For example: SO3 + H2O = H2SO4 - the manifestation of acidic properties; CaO + H2O = Ca (OH) 2 - manifestation of basic properties;

Periodic table of Mendeleev, as an indicator of acid-base properties

The Mendeleyev table can help in determiningacid-base properties of elements. If you look at Mendeleyev's table, you can see such a regularity that the non-metallic or acidic properties are amplified horizontally from left to right. Accordingly, closer to the left edge are metals, in the center are amphoteric elements, and on the right are nonmetals. If we look at the electrons and their attraction to the nucleus, it is noticeable that in the left part the elements have a weak nuclear charge, and the electrons are at the s-level. As a result, these elements are easier to give an electron than to the elements on the right. Non-metals have a sufficiently high nuclear charge. Thus, the recoil of free electrons becomes more complicated. Such elements are easier to attach to themselves electrons, showing acid properties.

Three theories for defining properties

There are three approaches that determine whichproperties has a compound: the proton theory of Bronsted-Lowry, the aprotic electron theory of Lewis, the theory of Arrhenius. According to the proton theory, acid compounds are capable of giving out their protons. Such compounds were called donors. And the main properties are manifested by the ability to accept or attach a proton. The aprotic approach implies that accepting and donating protons to determine acid-base properties is not necessary. Acidic properties in this theory are manifested by the possibility of adopting an electron pair, and the main ones, on the contrary, give this pair. The Arrhenius theory is the most relevant for determining the acid-base properties. In the course of the study, it was proved that acidic properties are manifested when, during the dissociation of aqueous solutions, the chemical compound is divided into anions and hydrogen ions, and the main properties - to cations and hydroxide ions.