The formula weight of the compound Al2(SO4)3.18H2O is 666g/mol.
The formula weight of a compound can be calculated by summing the atomic masses of each element that constitutes the compound.
The compound Al2(SO4)3.18H2O consists mainly of Aluminum, sulphur, oxygen, hydrogen elements.
Al2(SO4)3.18H2O = 27(2) + (32 + 16(4))3 + 18 (18)
54 + 288 + 324 = 666g/mol
Therefore, the formula weight of the compound Al2(SO4)3.18H2O is 666g/mol.
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