What does the symbol for a double bond look like? 

What colour does brown bromine water go when it mixes with a chemical that has double bonds in it? 

What can be used as a simple test for the double bonds in alkenes? 

Which of these is the standard formula for an alkene? 

In this structural formula, which part is a double bond? 

Which of these is the name of an alkene with 10 carbons in its chain?