Is Tollen's test safe?

Tollen's test is an important test to distinguish between aldehyde and ketone.

$$\ce{2 [Ag(NH3)2]+ + RCHO + H2O → 2 Ag(s) + 4 NH3 + RCO2H + 2 H+}$$

But is this reaction safe? Is there any threat in the formation of silver nitride (fulminating silver)? It is formed when the products of most of the reaction of silver($\ce{I}$) salts are kept aside undisturbed. It act as a potential explosive or a contact explosive. If there is any threat in the formation of silver nitride, what precaution must be taken to prevent it?

• Great question - In general I'd say that not enough attention is given to safety. A good chemist has a plan to dispose of excess reagents as well as the various waste reaction products. – MaxW Jan 8 '16 at 18:14

1 Answer

The Tollen's test is safe, but silver amine solutions should be prepared as needed just before use. The formation of explosive silver nitride is a slow process and can be prevented by treating the solution with mineral acid after use.

• I agree, but it would be nice if you add an equation or link and elaborate a little – Mithoron Jan 8 '16 at 17:20
• See here for a more detailed answer. – Nilay Ghosh Feb 4 at 10:10