JEE Main & Advanced Sample Paper JEE Main - Mock Test - 6

  • question_answer
    Consider the following statements -
    [A] In the Aluminothermite process, aluminium acts as reducing agent.
    [B] The process of extraction of gold involves the formation of \[{{[Au{{(CN)}_{2}}]}^{-}}\] and \[{{[Zn{{(CN)}_{4}}]}^{2-}}\].
    [C] In the extractive metallurgy of zinc, partial fusion of \[ZnO\]with coke is called sintering and reduction of ore to the molten metal is called smelting.
    [D] Extractive metallurgy of silver from its ore argentite involves complex formation and displacement by more electropositive metal.
    Choose the correct options -

    A) A and B

    B) B and C

    C) A, B and C     

    D) A, B, C and D

    Correct Answer: D

    Solution :

    [A] \[C{{r}_{2}}{{O}_{3}}+2Al\xrightarrow{{}}\overset{+3}{\mathop{A{{l}_{2}}}}\,{{O}_{3}}+2Cr\]
    [B] \[Au+2C{{N}^{-}}+{{H}_{2}}O+\frac{1}{2}{{O}_{2}}\] \[\xrightarrow{{}}{{[Au{{(CN)}_{2}}]}^{-}}+2O{{H}^{-}}\]\[2{{[Au{{(CN)}_{2}}]}^{-}}+Zn\to {{[Zn{{(CN)}_{4}}]}^{2-}}+2Au\]
    [C] Statement is true
    [D] \[A{{g}_{2}}S+4NaCN\xrightarrow{{{O}_{2}}}2Na[Ag{{(CN)}_{2}}]+N{{a}_{2}}S\]

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