What is the Rock Cycle? Like most Earth materials, rocks are created and destroyed in cycles. The rock cycle is a model that describes the formation, breakdown, and reformation of a rock as a result of sedimentary, igneous, and metamorphic processes. All rocks are made up of minerals. A mineral is defined as a naturally occurring, crystalline solid of definite chemical composition and a characteristic crystal structure.
It isn't illegal to chew gum, but it is illegal to bring them into Singapore or sell them except for medical purposes. Since you can't buy gum (selling is illegal) there's no way to chew them so it's almost as good as not being able to chew gum. http://www.customs.gov.sg/leftNa...
Question: What Is in Chewing Gum? Answer: Originally, chewing gum was made from the latex sap of the sapodilla tree (native to Central America). This sap was called chicle. Other natural gum bases may be used, such as sorva and jelutong. Sometimes beeswax or paraffin wax is used as a gum base. After World War II, chemists learned to make synthetic rubber, which came to replace most natural rubber in chewing gum (e.g., polyethylene and polyvinyl acetate).