Question

Ferrous oxide has a cubic structure and each edge of the unit cell is 5.0. Assuming density of the oxide as 4.0 g/cm-3, then the number of Fe2+ and O2- ions present in each unit cell will be

Solution

Correct option is

FourFe2+ and four O2-

 

Let the units of ferrous oxide in a unit cell = n. Molecular weight of ferrous oxide (FeO)

                          = 56 + 16 = 72g mol-1

Weight of n unit =     

Volume of one unit = (length of corner)3 
                                

  
    

    

    

                                            = 4.27 = 4

SIMILAR QUESTIONS

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Q8

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Q9

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Q10

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