Q18 of 68 Page 21

An element with molar mass 2.7×10-2 kg mol-1 forms a cubic unit cell with edge length 405 pm. If its density is 2.7×103 kg m-3, what is the nature of the cubic unit cell?

Given information:-

Molar mass of the element = 2.7×10-2 kg mol-1


Edge length, a = 405 pm


Density, d = 2.7×103 kg m-3


Using the formula, d


Putting the values given at their appropriate place, we get



= 3.99 which is approximately equal to 4


Therefore, it is an fcc unit cell.


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