Question 4 • Chemistry A.1 - F26 - Jacob Metsker
An Arrhenius acid increases the concentration of H⁺ ions when dissolved in water. HCN ionizes in water to produce H⁺ and CN⁻, so it is an Arrhenius acid. NH₃ and Mg(OH)₂ are bases, while BF₃ is a Lewis acid rather than an Arrhenius acid.
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