In the following Questions, the Assertion and Reason have been pu… - Vidyadip

MCQ

In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: $23g$ of Na contains $6.022 \times 10^{23}$ sodium atoms.
Reason: $23g$ of Na contains $1$ atom of Na.

✓
Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
B
The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.
C
Assertion is true but the Reason is false
D
The statement of the Assertion is false but the Reason is true.

✓

Answer

Correct option: A.

Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

One mole contains $6.023 \times 10^{23}$ chemical units.
$23g$ of Na atom
atomic mass of $Na = 23u$
Number of particles=Number of Moles$ × N$
$\Rightarrow\Big(\frac{\text{Given weight}}{\text{Gram atomic weight}}\Big)\times6.023\times10^{23}$
$\Rightarrow\Big(\frac{23}{23}\Big)\times6.023\times10^{23}$
$\Rightarrow1\times6.023\times10^{23}$
$\Rightarrow6.023\times10^{23}$ Na particles

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