Answer is c...............
卂几丂山乇尺
As the name indicate that in 1-octene there is a double bond on the first position in the eight carbon atoms chain THUS to detect its presence, we use bromine water test;
Add bromine water to the test tube containing octane/octene if the brown colour of bromine water disappears then octene is present.
Na releases 1 electron to be stable
Cl requires 1 electron to be stable
both are ionic bonded to be stable
