3.5 I can recall the reaction of methane and bromine

Alkanes react with liquid bromine in the presence of UV


Explain why this condition is necessary
Energy is needed for bromine to break. The UV lights tickle the bromine, causing them to gain more energy and eventually breaking them
What is this type of reaction called?
Substitute reaction
State and explain the observation
Liquid bromine changes color from brown/red to colorless. This is because the bromine turns into bromine radacles after they break apart.. Hydrogen bromide is colorless
Draw the displayed formula of the reaction between methane and bromine 

Write out a balanced (with state symbols) the reaction between ethane and chlorine
CL2(L) --> C2H5Cl+ HCL
State and explain the observation in this chemical reaction
Ethane goes from yellow green to colorless.