[tex]\footnotesize\implies Number \: of \: moles = \dfrac{Molecules}{Avogadro's \: number} [/tex]
[tex]\footnotesize\implies Number \: of \: moles = \dfrac{Given \: mass}{Gram \: molecular \: mass} [/tex]
Equate both the equations:
[tex]\footnotesize\implies \dfrac{Molecules}{Avogadro's \: number} = \dfrac{Given \: mass}{Gram \: molecular \: mass} [/tex]
Gram molecular mass of the given compund:
[tex]\footnotesize\implies CCl_2F_2 =12 + 35.5 \times 2 + 18 \times 2 [/tex]
[tex]\footnotesize\implies CCl_2F_2 =12 + 71 + 36[/tex]
[tex]\footnotesize\implies CCl_2F_2 =119 \: g[/tex]
Now, substitue the known values in the given formula:
[tex]\footnotesize\implies \dfrac{Molecules}{Avogadro's \: number} = \dfrac{Given \: mass}{Gram \: molecular \: mass} [/tex]
• Molecules = 7.66×10¹⁹
• Avogadro's number = 6.022 × 10²³
• Gram molecular mass = 119 g
• Mass = ?
[tex]\footnotesize\implies \dfrac{7.66 \times {10}^{19} }{6.022 \times {10}^{23} } = \dfrac{Given \: mass}{119} [/tex]
[tex]\footnotesize\implies \dfrac{7.66 \times {10}^{19} \times {10}^{ - 23} }{6.022 } = \dfrac{Given \: mass}{119} [/tex]
[tex]\footnotesize\implies 1.272 \times {10}^{ -4} = \dfrac{Given \: mass}{119} [/tex]
[tex]\footnotesize\implies Given \: mass = 1.272 \times {10}^{ -4} \times 119 \\ [/tex]
[tex]\footnotesize\implies Given \: mass =151.368 \times {10}^{ - 4} [/tex]
[tex]\footnotesize\implies Given \: mass =1.51368 \times {10}^{ - 2} \times {10}^{ - 4}[/tex]
[tex]\footnotesize\implies \bf Given \: mass =1.51368 \times {10}^{ - 6} \: g \:mol[/tex]
