Question

the unit cell of a mettalic element is face centred cubic and the side of the cube is 540.2pm. calculate the density of a metal in gcm-3 is if it's relative atomic mass is 202.4.

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Answer 1

Answer:

Given:

Edge of cube, a = 540.2 pm = 540.2 × 10⁻¹⁰ cm

Atomic mass, M = 202.4 gm

The unit cell is FCC.

To Find:

The density of the metal.

Calculation:

- For FCC, z = 4

- We know the formula:

V × NA × d = z × M

⇒ a³ × NA × d = z × M

⇒ d = (z × M)/(a³ × NA)

⇒ d = (4 × 202.4)/{(540.2 × 10⁻¹⁰)³ × 6.022 × 10²³)

⇒ d = 809.6/(157.64 × 10⁻²⁴ × 6.022 × 10²³)

⇒ d = 809.6/94.93

⇒ d = 8.528 gm/cm³

- So, the density of the given metallic element is 8.528 gm/cm³

Explanation:

Answer 2

Answer:

Yes, the above answer is correct