Chemistry - Complete d-block Question with Solution | TestHub

A solution of colourless salt $\mathrm{H}$ on boiling with excess $\mathrm{NaOH}$ produces a non-flammable gas. The gas evolution ceases after sometime. Upon addition of $\mathrm{Zn}$ dust to the same solution, the gas evolution restarts. The colourless salt (s) $\mathrm{H}$ is (are)