Question

What is the Wt% of SiO2 in augite?

(Ca, Fe, Mg, Na)(Mg,Fe,Al) (Si,Al)2 O6

Answer 1

The weight% of
`SiO_2` in augite is 13.16 %.

Step-by-step explanation:

Atomic mass of calcium = 40 g/mol

Atomic mass of iron = 56 g/mol

Atomic mass of magnesium = 24 g/mol

Atomic mass of sodium = 23 g/mol

Atomic mass of aluminum = 27 g/mol

Atomic mass of silicon = 28 g/mol

Atomic mass of oxygen = 16 g/mol

Mass of
`SiO_2=28 g/mol+ 2\time 16 g/mol=60 g/mol`

Molar mass of the augite
`(Ca, Fe, Mg, Na)(Mg,Fe,Al)(Si,Al)_2 O_6` = M

`M=40 g/mol+2* 56 g/mol+2* 24 g/mol+23 g/mol+3* 27 g/mol+2* 28 g/mol+6* 16 g/mol=456 g/mol`

Weight% of
`SiO_2` in augite:

`w\%=(60 g/mol)/(456 g/mol)* 100=13.16\%`