Question

Ratio of number of atom per unit cell in the bcc and fcc?

Answer 1

Answer :

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✴ No. of atoms and their contribution per unit cell :

⇒ At corner = 8 × 1/8

⇒ At faces = 0

⇒ In centre = 1

✴ Total no. of atoms per unit cell :

⇒ 1 + 1 = 2

◕ Packing efficiency = 68%

◕ Co-ordination no. = 8

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✴ No. of atoms and their contribution per unit cell :

⇒ At corner = 8 × 1/8

⇒ At faces = 6 × 1/2

⇒ In centre = 0

✴ Total no. of atoms per unit cell :

⇒ 1 + 3 = 4

◕ Packing efficiency = 74%

◕ Co-ordination no. = 12

Ratio :-

➝ BCC / FCC = 2 / 4

➝ BCC : FCC = 1 : 2

Answer 2

Answer: This may help you

Explanation:

The ratio of the number of atom per unit cell in the bcc and fcc is: (A) 1:2 - The term bcc means Body Centered Cubic unit cell. - In it, the total no of atoms per unit cell is 2.