In aqueous acidified solution, CrO$_4^{2-}$ ion converts to which of the following ?
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- CrO$_3$
- Cr$^{3+}$
- Cr$_2$O$_7^{2-}$
- CrO
The Correct Option is C
Solution and Explanation
Step 1: Nature of chromate ion. Chromate ion is: \[ CrO_4^{2-} \] It is yellow in colour.
Step 2: Effect of acidification. When acid is added: \[ [H^+] \] increases. According to Le Chatelier's principle, the equilibrium shifts in the forward direction. \[ 2CrO_4^{2-}+2H^+ \rightarrow Cr_2O_7^{2-}+H_2O \]
Step 3: Product formed. The product formed is dichromate ion: \[ Cr_2O_7^{2-} \] which is orange in colour.
Step 4: Final answer. \[ \boxed{Cr_2O_7^{2-}} \] Hence option (C) is correct.
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