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Grade upto college level Physical Chemistry

You are given marbles of diameter 10 mm. They are to be placed such that their centres are lying in a square bound by four lines each of length 40 mm. What will be the arrangements of marbles in a plane so that maximum number of marbles can be placed inside the area? Sketch the diagram and derive expression for the number of molecules per unit area.

Profile image of Shane Macguire
12 Years agoGrade upto college level
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2 Answers

Profile image of Deepak Patra
12 Years ago
Hello Student,
Please find the answer to your question
The area of square = 4 * 4 = 16 cm2
Again to have the maximum number of spheres the packing must be hcp.
Maximum number of spheres = 14 + 8 = 14 + 4 = 18
full half
233-1787_25.jpg
Area = 16 cm2
∴ Number of spheres cm2 = 18/16
= 1.126

Thanks
Deepak patra
askIITians Faculty
Profile image of Himanshu singh
8 Years ago
marble of diameter 10mm each are to be arranged on a flat surface so that their center lie with the area enclosed by four linws of length each 40mm. sketch the arrangement that will give the maximum number of marble per unit area, that can be enclosed in this manner and deduce the expression to calculate it. chemistry question iit jee