The density of lead, which has the FCC structure, is 11.36 . The atomic weight of lead is 207.19 . Use Avogadro's number: 6.02210. Calculatethe lattice parameter(Enter your answer to three significant figures.) = 2.75*10^21 the atomic radius of lead(Enter your answer to three significant figures.) =

Respuesta :

Answer:

a

[tex]a_o  = 4.95 *10^{-8} \  cm  [/tex]

b

[tex]r =  1.7500 *  10^{-8} \  cm[/tex]

Explanation:

From the question we are told that

   The  density of  lead is  [tex]\rho_l =  11.36 \  g/cm^3[/tex]

   The atomic weight is  [tex]M_w  =  207.19 \  g/mol[/tex]

    The  Avogadro's number is  [tex]N_a  =  6.022 *  10^{23} \  \frac{atom}{mol}[/tex]

Generally for FCC the number of  atom is  n  =  4

 Generally the volume of a unit FCC cell is mathematically represented

          [tex]V =  \frac{n  *  M_w }{N_a  *  \rho_l }[/tex]

          [tex]V =  \frac{4  *  207.19 }{ 6.022 *  10^{23}  *  11.36 }[/tex]

         [tex]V = 1.211 5 *10^{-22} \  cm^3[/tex]

Generally the lattice parameter is mathematically represented as

      [tex]a_o  = \sqrt[3]{V } [/tex]

     [tex]a_o  = \sqrt[3]{1.211 5 *10^{-22} } [/tex]

=>   [tex]a_o  = 4.95 *10^{-8} \  cm  [/tex]

Generally the radius of the lead is mathematically represented as

        [tex]r =  \frac{a_o  *  \sqrt{2}  }{4}[/tex]

=>      [tex]r =  \frac{4.95 *10^{-8}  *  \sqrt{2}  }{4}[/tex]

=>      [tex]r =  1.7500 *  10^{-8} \  cm[/tex]