Assertion :First period of periodic table is shortest period. Reason: A K shell can accommodate a maximum of two electrons.

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

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Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

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Assertion is correct but Reason is incorrect

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Assertion is incorrect but Reason is correct

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Solution

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
First period of periodic table contains only $2$ elements as the k shell gets completely filled at end of first period and it can accommodate only $2$ electrons.

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ASSERTION: n-Pentane and n-Hexane belong to a homologous series.

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Assertion (A) Order of the reaction can be zero or fractional.

Reason (R) We cannot determine order from balanced chemical equation.

(a) Both assertion and reason are correct and the reason is correct explanation of assertion
(b) Both assertion and reason are correct, but reason does not explain assertion.
(c) Assertion is correct, but reason is incorrect
(d) Both assertion and reason are incorrect
(e) Assertion is incorrect but reason is correct.

Assertion: All the points (1, 0), (-1, 0), (2, 0) and (5, 0) lie on the x – axis.
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Choose the correct option.

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Assertion :First period of periodic table is shortest period. Reason: A K shell can accommodate a maximum of two electrons.

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for AssertionFirst period of periodic table contains only 2 elements as the k shell gets completely filled at end of first period and it can accommodate only 2 electrons.

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
First period of periodic table contains only $2$ elements as the k shell gets completely filled at end of first period and it can accommodate only $2$ electrons.