Which of the following test would be most useful in differentiating butanal, and benzaldehyde.
Which of the test compounds (Acetone,acetaldehyde,benzaldehyde or cyclohexanone) should react in the same way as butanal in these tests?

2.which one of these reagents reacts differently with benzaldehyde than it did with benzaldehyde than it did with other aldehydes?

Think you need to do some lab work or re read your textbook.