Question

Assertion :One mole of helium corresponds to 'N' He atoms whereas one, mole of hydrogen corresponds to '2N' hydrogen atoms. Reason: One mole of hydrogen corresponds to 'N' molecules of hydrogen.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

let $N$ be the no. of $molecule$ present in one mole of Hydrogen

= $6.022$×${10}^{23}$

and,

the no. of $Atom$ present in one mole of Hydrogen

=$2$×$6.022$×${10}^{23}$ = $2N$

as the formula of Hydrogen gas is $H_2$.

Now the formula of Helium gas is $He$

we cannot calculate no. of a molecule of Helium because it doesn't make the bond with any element

so,

No.of $atom$ present in one mole of helium is $6.022$×${10}^{23}$ = $N$

from above we can conclude that Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

Hence option A is correct.