Crystallography

Identify the right statement for an amorphous substance ?

• Polyhedral form

• No external and internal structure

• Have a internal structure but do have external structure

• Covering smooth surfaces

Which of the following is correct prder of rainbow colour?

• VIBGYOR

• BIVGYOR

• VIBYGOR

• VIBGYRO

How many crystal systems are there in crystallography?

• 2

• 14

• 7

• 132

A certain type of crystal is having lattice constants in the ratio a : b : c is 0.424 :1: 0.367 . The Miller indices

of the plane whose intercepts are 0.212 : 1 : 0.183 is

• (212)

• (112)

• (211)

• (111)

The atomic packing fraction (APF) of FCC crystal is:

• 68%

• 34%

• 74%

• 52%

which structure is this?

• Graphite

• NaCl

• CsCl

• Diamond