MCQ
For two statements are given$-$one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below:
Assertion: A lead nitrate on thermal decomposition gives lead oxide, brown coloured nitrogen dioxide and oxygen gas.
Reason: Lead nitrate reacts with potassium iodide to form yellow ppt. of lead iodide and the reaction is double displacement as well as precipitation reaction.
  • A
    Both $A$ and $R$ are true, and $R$ is correct explanation of the assertion.
  • Both $A$ and $R$ are true, but $R$ is not the correct explanation of the assertion
  • C
    $A$ is true, but $R$ is false.
  • D
    $A$ is false, but $R$ is true.

Answer

Correct option: B.
Both $A$ and $R$ are true, but $R$ is not the correct explanation of the assertion
Decomposition reaction is a reaction in which a compound breaks down into two or more simpler substances.
$\ce{2Pb(NO_3)_2 \rightarrow 2Pb0 + 4NO_2 + O_2}$

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