The flame in an operational bunsen burner undergoes a

 The flame in an operational Bunsen burner undergoes a
A. phase change
B. nuclear change
C. chemical change
D. physical change

Flames are a chemical change since you cannot separate the components physically once you've combined them so the answer is C. chemical change

By definition, energy is the "ability to do work." Together with the quantity of mass, energy is considered to be a scalar vector wherein it only describes magnitude. On the other hand, force is a vector quantity consisting of both magnitude and direction. Therefore, the force should be used predominantly since it is a vector quantity.