In the following reactions, ZnO is respectively acting as a /an ?

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1 Answer
Mar 28, 2018

#"Na"_2"O"# is a good base, e.g.

#"Na"_2"O"(aq) -> 2"Na"^(+)(aq) + "O"^(2-)(aq)#,

since #"O"^(2-)# is the conjugate base of the strong base #"OH"^(-)#. So, #"ZnO"# must be acting as an acid in the first reaction.

The second reaction is the reverse of a carbonate decomposition. Also, #"CO"_2# is a nice Lewis acid; it has an antibonding orbital on the carbon that can accept electron density from the partially negative #"O"# on #"ZnO"#, so #"ZnO"# must be a base in this reaction.

In fact, #"ZnO"# is a common amphoteric oxide.