|MadSci Network: Chemistry|
Re:Must the products of a neutralization reaction be a salt and water only? In reaction 1: PbO2 + 4HCl -> PbCl2 + 2H2O + Cl2, the oxidation state of elements of Pb and Cl change from +4 and -1 to +2 and 0, respectively. So this is an oxidation-reduction reaction, not a neutralization reaction. PbO2 is reduced by HCl to PbCl2. In reaction 2: PbO + 2HNO3 -> Pb(NO3)2 + H20, no element has change its oxidation state. It is a neutralization reaction. PbO just behaves as a base, HNO3 as an acid. Whether a reaction is a neutralization one is judged according to the oxidation state change, not products, although the products of a neutralization reaction only include salts and water. Some oxidation-reduction reaction also only has salt and water products. Reference: Inorganic Chemistry. Ed. by Xizhang Cao et al. Higher Education Press:Beijing. Dan Berger adds: Another example of a redox reaction giving salt/water products is the bleach oxidation of alcohols: R2CHOH + NaOCl -> R2C=O + NaCl + H2O This is an oxidation because the organic molecule has been oxidized from an alcohol to a ketone.
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