Question

Gold (at wt. 197g mol-1) crystallises is a cubic closest packed structures (the face – centred cubic) and has a density of 19.3g/cm2. Its atomic radius is

Solution

Correct option is

144.17 pm

 

Mass of unit cell containing four atoms

    

= 1.31 × 10-21 g/unit cell

     

= 6.78 × 10-29 m3

Volume,     V = a3

                      

                       = 407.76 pm

    

                              = 144.17 pm

Alternative 

                              

                              

                              a = 407.8 × 10-10 m

                                 = 407.8 pm

                              

SIMILAR QUESTIONS

Q1

The composition of a sample of wustite is Fe0.93 O. What percentage of the iron is present in the form of  Fe III?

Q2

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Q3

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Q4

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Q5

 

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The ratio of the side of the unit cell for NaCI to that for KCI is

Q6

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Q7

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Q8

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Q9

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Q10

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