Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A sample of 0.58 g of propanal, (), is divided so that the whole amount is tested twice, once with excess Tollens' reagent and once with excess Fehling's solution. Each aldehyde molecule gives two silver atoms with Tollens' reagent and one formula unit of copper(I) oxide, (), with Fehling's solution. Use Ag = 108 in g/mol. Find the amount of propanal, the mass of silver that forms and the mass of copper(I) oxide that forms.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. .
Step 2. Silver. of Ag. The mass is .
Step 3. Copper(I) oxide. .
Answer: , and .
Check. The silver is twice the amount of aldehyde in moles, and the copper(I) oxide is one times.
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Bromine adds across one double bond for each molecule of , and a phenol takes three. Tollens' reagent gives for each , and Fehling's solution gives one . The iodoform test is positive for and .