1800-150-456-789
FlagBACK
Flag AIIMS MBBS> A metallic element crystallises into a la...
question mark

A metallic element crystallises into a lattice containing a sequence of layers ABABAB.... Any packing of spheres leaves out voids in the lattice. Percentage of empty space (by volume) is
  1. 52%
  2. 48%
  3. 50%
  4. 74%

Abhishek Dogra , 6 Years ago
Grade 11
anser 1 Answers
Arun

Last Activity: 6 Years ago

Dear student
 
For a hcp unit cell, there are 6 atoms per unit cell. If r is the radius of the metal atoms, volume occupied by the metallic
Atoms 6 * 4/3 * π * r3 = 6 * 1.33 * 22/7 * r3 = 25.08 * r3
Geometrically it has been shown that the base area of hcp unit cell
= 6 * √3/4 * 4r2 and the height = 4r * √2/3
∴ Volume of the unit cell
= Area * height = 6 * √3/4 * 4r2 * 4r * \sqrt{\frac{2}{3}}= 33.94 r3
∴ Volume of the empty space of one unit cell
= 33.94 r3 – 25.08 r3 = 8.86 r3
∴ Percentage void = 8.816 r3/33.94 r3 * 100 = 26.1%
 
Regards
Arun
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments


Other Related Questions on aiims mbbs

question mark
most scoring topics for neet?for all the subjects : chemisrtry,biology and physics
aiims mbbs
1 Answer Available

Last Activity: 2 Years ago

question mark
Consider the situation shown in figure. The strings are massless and pulley is fixed and frictionless. The speed of 3 kg mass just before touching the ground is (g = 10 m s-²)
aiims mbbs
1 Answer Available

Last Activity: 3 Years ago

question mark
Hi! My son would be taking his exam in May 2022. We need some counseling as to how to go about it as an NRI? 
 
 
aiims mbbs
1 Answer Available

Last Activity: 3 Years ago

question mark
I am not diagnosed with Schizoaffective disorder. I am recently diagnosed with Bipolar 1 disorder (most recent or current manic) along with the symptoms of grandiose delusions (According to the psychiatrist, I believe myself I am God). I am not diagnosed with schizoaffective disorder but I had taken Olanzapine (increased to 5 mg dosage) and this drug is used to treat Schizophrenia but as prescribed by Psychiatrist, I was taking Olanzapine not for Schizoaffective disorder but for Bipolar disorder along with delusions. Another Psychiatrist from Lybrate platform told me that, "you might be suffering from schizoaffective disorder, and it requires immediate action of a doctor. Consult a psychiatrist as soon as possible." So, does this mean that I am diagnosed with Schizoaffective disorder or suffering from Schizoaffective disorder? If I really have Schizoaffective disorder, then who will marry me? It's better to commit Suicide as Schizoaffective disorder is the most critical psychological disorder. Does the psychiatrist indirectly told me that I am having Schizoaffective disorder in the form of Bipolar 1 disorder along with grandiose delusions symptoms?
aiims mbbs
1 Answer Available

Last Activity: 3 Years ago

question mark
100 ml of gaseous hydrocarbon consumes 300 ml of oxygen for complete combustion. the hydrocarbon is
aiims mbbs
0 Answer Available

Last Activity: 3 Years ago