Which of the following ions does not liberate hydrogen gas on reaction with dilute acids ?

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1 Answer
Mar 5, 2018

Mn^(2+) does not liberate hydrogen gas on reaction with dilute acids

Explanation:

These are transition metals and reactivity decreases as we move from Ti^(2+) to V^(2+) to Cr^(2+) and finally Mn^(2+) in the fourth row of periodic table. As such Mn^(2+) does not liberate hydrogen gas on reaction with dilute acids.