Question

The density of aluminum is 2.7 g/cm3 and that of Al2O3 is about 4 g/cm3. Calculate the PB ratio for Aluminum. (Hint: The Pilling-Bedworth Ratio (PBR) gives the volume of oxide formed to the volume of metal atoms.)

a) 1.28
b) 0.28
c) 0.75

Answer 1

1.28

Step-by-step explanation:

Al = aluminium

Density of Al = 2.7g/cm³

Density of Al2O3 = 4g/cm³

Molecular weight of Aluminum = 27g/mol

Molecular weight of Al2O3= 101.96 g/mol

Pilling bedworth ratio = Rob

= M(Al2O3) * density of Al / n* molecular weight of Al * density of Al2O3

= 101.96g/mol x 2.7g/cm³/2x 27g/mol x 4g/cm³

= 275.292/216

= 1.28

From the calculation above 1.38nis the PB ratio for aluminum