Unsaturation in organic compounds is detected by ...........

$A$ single compound of the structure $CH_3-CO-CH_2-CH_2-CH_2-CHO$ is obtainable from the ozonolysis of which of the following cyclic compounds?

The order of increasing reactivity towards $HCl$ of the following compounds will be:
$(1)$ $CH_2 = CH_2$
$(2)$ $(CH_3)_2C = CH_2$
$(3)$ $CH_3CH = CHCH_3$

What is produced when chlorine is passed through propene at $400\,^oC$?

When glycerol is heated with concentrated sulfuric acid,a substance with a pungent smell is obtained. Which of the following is that compound?

The reaction of ethylene with bromine in a methanol solution yields $1, 2-$dibromoethane as well as $BrCH_2CH_2OCH_3$. This is because ......