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 $\ce{(a), (b), (c)}$ and $(d)$ as given below :
Assertion : According to Mendeleev's periodic law, the properties of elements is the periodic function of their atomic numbers.
Reason : Mendeleev placed some elements with higher atomic mass before the elements with lower atomic mass.
  • A
    Both $A$ and $R$ are true, and $R$ is correct explanation of the assertion.
  • B
    Both $A$ and $R$ are true, but $R$ is not the correct explanation of the assertion.
  • C
    $A$ is true, but $R$ is false.
  • $A$ is false, but $R$ is true.

Answer

Correct option: D.
$A$ is false, but $R$ is true.
According to Mendeleev's periodic law, the properties of elements are the periodic function of their atomic masses.

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