What is the mass of acetic aldehyde reacted “silver mirror”, if it formed 16.05 g of silver?

the number of moles of silver = 16.05 / 108 = 0.15 mol
the number of moles of acetic aldehyde = 0.15 / 2 = 0.075 mol
mass of acetic aldehyde = 0.075 * 44 = 3.3 g

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