When foul-smelling Hydrogen Sulphide () gas is bubbled through a strongly acidified, orange solution — d and f Block Elements Chemistry Question

💡 Solution & Explanation

Dichromate is a potent oxidizer in acid. It oxidizes the $-2$ sulfur in $H_2S$ directly to neutral, elemental sulphur ($S^0$), which appears as a fine yellow-white turbidity. Simultaneously, the orange $Cr^{6+}$ is reduced to green $Cr^{3+}$.