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Which common compounds are acids in aqueous solution?

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Two diagrams show the three-dimensional structure of a methane molecule: panel A uses a ball-and-stick model with a central carbon atom connected to four hydrogen atoms in a tetrahedral arrangement, while panel B illustrates the bond angle of 109.5 degrees and bond length of 1.09 angstroms between carbon and hydrogen atoms. — chemical compound Methane, in which four hydrogen atoms are bound to a single carbon atom, is an example of a basic chemical compound. The structures of chemical compounds are influenced by complex factors, such as bond angles and bond length.

In chemistry, an acid is a substance that, when dissolved in water, increases the concentration of hydronium ions ( $H_{3} O^{+}$ ) and typically exhibits properties such as a sour taste, the ability to turn blue litmus paper red, and the capacity to react with bases to form salts.123

Common compounds that function as acids in aqueous solution include:

Mineral Acids: These include hydrochloric acid (HCl), sulfuric acid ( $H_{2} S O_{4}$ ), nitric acid ( $H N O_{3}$ ), phosphoric acid ( $H_{3} P O_{4}$ ), and perchloric acid ( $H C l O_{4}$ ).1345
Organic Acids: These include carboxylic acids, such as acetic acid ( $C H_{3} C O O H$ ).134
Other Common Acids: These include hydrofluoric acid (HF), hydrobromic acid (HBr), hydroiodic acid (HI), hydrocyanic acid (HCN), hydrosulfuric acid ( $H_{2} S$ ), nitrous acid ( $H N O_{2}$ ), sulfurous acid ( $H_{2} S O_{3}$ ), and carbonic acid ( $H_{2} C O_{3}$ ).4

These substances contain hydrogen atoms that are released as positively charged hydrogen ions in solution. While many acids are inorganic, amino acids are a notable class of compounds that can function as both acids and bases depending on the environment.13