Chemical Tests

Question 1

2,4-DNPH

Answer 1

Test for carbonyls, an orange crystalline precipitate will form

Question 2

Dichromate & H+

Answer 2

Test for alcohols and aldehydes, goes from orange to green

Question 3

PCl5

Answer 3

Test for OH group, steamy fumes and vigorous effervescence

Question 4

I2 and NaOH

Answer 4

Iodoform test, tests for methyl ketones, methyl secondary alcohols, ethanal and ethanol. Makes a carboxylate salt (O- where methyl group was)

Question 5

Tollens (ammonical silver nitrate)

Answer 5

Test for aldehydes, silver mirror forms or black ppt

Question 6

Fehling’s solution

Answer 6

Test for aldehyde, goes from blue to red (Cu2+ —> Cu2O)