A compound contains 54 g of Al and 48 g of O. What is its empirical formula? (Al = 27, O = 16)
Answer and explanation
Correct answer: A. AlO
- Step 1: Moles of Al ; moles of O .
- Step 2: Divide by the smaller number: the ratio Al : O is .
- Step 3: Empirical formula: AlO.
Answer
AlO.
Why not the others: AlO: the ratio of moles is inverted. AlO: the masses are treated as equal numbers of atoms. AlO: the ratio is not simplified correctly.
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