The no. of atoms in face centred cubic and hexagonal unit cells respectively are (a)6,4(b)4,6(c)1,6(d)2,6no spamming !!

The no. of atoms in face centred cubic and hexagonal unit cells respec

1.	The no. of atoms in face centred cubic and hexagonal unit cells respectively are (a)6,4(b)4,6(c)1,6(d)2,6no spamming !!
Answer» The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.(1) The number of atoms contained in one simple cubic unit cell of monoatomic substance is 1.8 atoms are present at 8 CORNERS of a simple cubic unit cell. Each atom CONTRIBUTES one eigth to the unit cell. TOTAL contribution =8× 81 =1(2) The number of atoms contained in one face-centred cubic unit cell of monoatomic substance is 4.8 atoms are present at 8 corners of a fcc unit cell. Each atom contributes one eigth to the unit cell. Total contribution =8× 81 =16 atoms are present at 6 corners of a fcc unit cell. Each atom contributes one half to the unit cell. Total contribution =6× 21 =3Total number of atoms in one fcc unit cell =1+3=4.(3) The number of atoms contained in one body-centred cubic unit cell of monoatomic substance is 2.8 atoms are present at 8 corners of a bcc unit cell. Each atom contributes one eigth to the unit cell. Total contribution =8× 81 =11 atom is present at body centre of a bcc unit cell. The atom contributes fully to the unit cell. Total contribution =1× 11 =1Total number of atoms in one fcc unit cell =1+1=2.