Question

Calculate formula unit mass of Al2 [CO3 ]3.

Answer 1

atomic mass of Al=27 u
atomic mass of C=12 u
atomic mass of O=16 u
now formula unit mass=27 x 2+3 (12+16x 3)=54+3 (12+48)=54 + 180=234

Answer 2

Mass of Aluminum (Al) = 27 u
Mass of carbon (C) = 12 u
Mass of oxygen (O) = 16 u
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Now formula unit mass of Al₂(CO₃)₃ --->
2  x 27 + 3 x 12 + 16 x 3 x 3 = 54 + 36 + 144 = 234 u