Acids and Bases: formulas & examples
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Definition of an acid - The Arrhenius model Acids are compounds that can donate H+ ions in water solutions.The role of water is essential in this definition. Pure HF is not considered to be an acid. It must be dissolved in water to act like an acid. There are many different acids, but they all have something in common. They have hydrogen attached to a nonmetal from either group 6A or group 7A. This last idea makes it easier to identify acids. A key idea is that an acidic hydrogen atom must be bonded to one of these atoms Binary acids Binary acids are acids that have hydrogen combined with an atom form either group 7A or 6A. The examples of binary acids are
The oxy acids or ternary acids have their origins in oxides of the nonmetals like CO2(gas). The strange thing about this is that these nonmetal oxides form acids when they mix with water. These compounds are the villains that cause the acid rain problem. |
Polyprotic acids Acids with more than one acidic proton/hydrogen can release all of the protons. This means H2SO4 has two acidic hydrogens that can be released form each formula unit. Common polyprotic acids are as follows: sulfurous acid, H2SO3, sulfuric acid, H2SO4, carbonic acid, H2CO3, phosphoris acid, H3PO4, phoshorus acid, H3PO3
The (aq) means the particle is dissolved in water. The particle is in an aqueous mixture.
Non-acidic hydrogens There are many compounds that contain hydrogen atoms. These hydrogens are so tightly bonded to a non-metal atom that the H-atoms are not able to break away.This explains why compounds like butane are not acids even though there are many hydrogen atoms in the formula. In butane the hydrogen atoms are attached to carbon (a non-metal) which is in group 4A not the required 6A or 7A. The hydrogen atoms are strongly bonded to a nonmetal atom that doesn't attract electrons enough to stabilize a negative charge.
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Definition of a base Bases are compounds that can readily donate OH-1 ions in water solutions. The role of water is essential in this definition. Pure solids like NaOH must be dissolved in water to act like a base. There are many different bases, but they have something in common. They all have an OH1- and a metal. This last idea makes it easier to identify bases. Bases have a hydroxide ion combined with a metal. The examples of bases are:
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