Acidos y bases

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Acid: substance that dissociates in water to form hydrogen ions (H+) and anions.
Base: substance that dissociates into hydroxide ions (OH-) and cations.
Hydrogen and hydroxideions could form water, and the cations and anions form a salt.
Acids donate H+ while bases accept H+.
A Bronsted Lowry acid is a proton (H+) donor.
A Bronsted Lowry base is a proton (H+) acceptor.Acids react to form bases and vice-versa. The acid-base pairs related to each other in this way are called conjugate acid-base pairs.
To form a conjugate acid, add one H+ to its base; to form aconjugate base, remove one H+ from its acid.
Substances which can act as acids and bases in this way are said to be amphoteric or amphiprotic. (must have a lone pair of electrons)
A Lewis acid is anelectron pair acceptor. A Lewis base is an electron pair donor. (pair of free electrons)
Lewis acid-base reactions result in the formation of a covalent bond, which will always be a dative bond becauseboth the electrons come from the base.
Alkalis are bases that dissolve in water to form the hydroxide ion OH-.
Acids and bases can be distinguished using indicators.
Acids react with metal, basesand carbonates to form salts
(1) Acid + metal --> salt + hydrogen
(2) Acid + base --> salt + water
(3) Acid + carbonate --> salt + water + carbon dioxide
The position of theequilibrium defines the strength of an acid or a base.
If equilibrium lies to the right, the acid has dissociated fully and is said to be a strong acid. If equilibrium lies to the left, the acid hasdissociated only partially so it is said to be a weak acid. The strength of an acid is therefore a measure of how readily it dissociates in aqueous solution.
If equilibrium lies to the right, producing ahigh concentration of ions, there is a strong base. If there is a partial ionization, equilibrium lies to the left, the concentration of ions will be low; therefore it will be a weak base.
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