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Question
Which of the following statements is not correct?
Options
Copper liberates hydrogen from acids.
In its higher oxidation states, manganese forms stable compounds with oxygen and fluorine.
\[\ce{Mn^{3+}}\] and \[\ce{Co^{3+}}\] are oxidising agents in aqueous solution.
\[\ce{Ti^{2+}}\] and \[\ce{Cr^{2+}}\] are reducing agents in aqueous solution.
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Solution
Copper liberates hydrogen from acids.
Explanation:
Copper does not liberate hydrogen from acids.
\[\ce{Cu + 2H2SO4 -> CuSO4 + SO2 + 2H2O}\]
\[\ce{3Cu + 8HNO3 -> 3Cu (NO3)2 + 2NO + 4H2O}\]
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