One form of asbestos called chrysotile is considered to be a human carcinogen. Mass analysis reveals that it has the empirical formula Mg₃Si₂H₄O₉. If the molar mass is 277 g/mol, which molecular formula is correct?

Question

Quizplus · Accepted Answer

To determine the molecular formula, we need to convert the empirical formula to a molecular formula by finding the molar mass of the empirical formula and dividing the molar mass of the compound by it. In this case, the empirical formula has a molar mass of 276.5 g/mol. Next, we divide the molar mass of the compound (277 g/mol) by the molar mass of the empirical formula (276.5 g/mol) to get a ratio of 1.0018. We can then multiply each subscript in the empirical formula by this ratio to get the molecular formula. The molecular formula that results is Mg1.0018S1.0018U1.0018B12.9823Si1.0018O1.0018H1.0018, which simplifies to MgS1.002SiO2H2. Therefore, choice C, Mg₃Si₂O₅(OH)₄, is the correct molecular formula.

One Form of Asbestos Called Chrysotile Is Considered to Be