The number of atoms in 8g of sodium is x $\times$ 1023. The value of x is ____________. (Nearest integer)
[Given : NA = 6.02 $\times$ 1023 mol$-$1
Atomic mass of Na = 23.0 u]
Answer (integer)
2
Solution
Given, mass of Na = 8g<br/><br/>Molar mass of Na = 23 gmol<sup>$-$1</sup><br/><br/>$${{Weight\,of\,sodium\,atom} \over {Molecular\,mass\,of\,sodium\,atom}} = {{Number\,of\,atoms} \over {Avogadro's\,number}}$$<br/><br/>${{8g} \over {23g}} = {{Number\,of\,atoms} \over {6.022 \times {{10}^{23}}}}$<br/><br/>Number of atoms $= {{8 \times 6.022} \over {23}} \times {10^{23}}$<br/><br/>Number of atoms = 2.09 $\times$ 10<sup>23</sup><br/><br/>x $\approx$ 2<br/><br/>Hence, answer is 2.
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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