Final answer:
The mass of impure 4-methoxybenzaldehyde and recrystallized 4-methoxybenzaldehyde can be calculated using the empirical formula mass.
Step-by-step explanation:
The mass of impure 4-methoxybenzaldehyde and recrystallized 4-methoxybenzaldehyde can be calculated using the empirical formula mass. The empirical formula for the compound is C5H7N, and the empirical formula mass is 81.13 g/mol. To find the mass, multiply the number of moles by the empirical formula mass. For example, if you have 0.5 moles of the compound, the mass of the impure or recrystallized form would be: 0.5 moles x 81.13 g/mol = 40.57 g.
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