Which test is positive?

You will write a small program that predicts the results of four tests from a short description of a compound. It uses what you know about Tollens' reagent, Fehling's solution, iodoform and 2,4-DNP.

The idea. Every aldehyde and ketone gives the 2,4-DNP solid. An aldehyde also gives Tollens' test. Fehling's test is given by aliphatic aldehydes only. The iodoform test needs a methyl group on the carbonyl carbon, or on a CH(OH) group.

Your tasks.

1. Complete tollens(c) so that it is true for an aldehyde.
2. Complete fehling(c) so that it is true for an aliphatic aldehyde.
3. Complete iodoform(c) so that it is true when the compound has a methyl group on its carbonyl carbon or its CH(OH) carbon.