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Assertion: Ag and Au are extracted by le...

Assertion: `Ag` and `Au` are extracted by leaching the ores with a dilute solution of `NaCN`.
Reason: Impurities associated with these ores dissolve in `NaCN`.

A

If both (A) and ( R) are correct and ( R) is the correct explanation of (A).

B

If both (A) and ( R) are correct, but ( R) is not the correct explanation of (A).

C

If (A) is correct, but ( R) is incorrect.

D

If (A) is incorrect, but ( R) is correct.

Text Solution

Verified by Experts

The correct Answer is:
C
Correct reason : `Ag` and `Au` dissolve in `NaCN` forming a soluble complex.
`4Ag+8NaCN+2N_(2)O+O_(2)rarr4Na[Ag(CN)_(2)]+4NaOH`
`4Au+8NaCN+2H_(2)O+O_(2)rarr4Na[Au(CN)_(2)]+ 4NaOH`.
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