Question

Calculate the formula unit mass of Aluminium Oxide (Al2o3)

Answer 1

a. 101.961 amu's 
b. 1.69 x 10^-22 
c. 4.0015, 408 divided by molar mass 
d. 3.437x10^18, moles times Avagadro's #, 6.022x10^23 
e.2, because one mol of Al2O3 breaks down into 2 Al 
f. 2 mol Al x 29.98g/mol = 60g

Answer 2

Formula unit mass of Aluminium Oxide:

Given:

Aluminium  Oxide(Ai2O3),

To find:

Calculate the formula unit mass.

Solution:

Mass of Aluminium oxide,

Ai2O3 = 0.034g,

Molar Mass = (2 x 27) + (3 x 16) = 56 + 48 = 102g mol -1,

Number of moles = mass / molar mass

= 0.034 / 102

= 0.0003 moles.

0.0003 moles of alumina contains,

0.0003 x 2 = 0.0006

Therefore,

The formula unit mass of Ai2O3 is = 0.034g.