What is the difference between a chemical change and a physical change? give an example of each.

Clyde and marilyn are riding a roller coaster. during which section(s) of the track is their potential energy converted to kinetic energy? a. from point b to point c only b. from point b to point d only c. from point a to point b only d. from point a to point b and from point c to point d

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)

The lewis diagrams for magnesium and fluorine are shown below. what is the correct chemical formula for magnesium fluoride? a. mgf b. mg2f c. mgf2 d. mg2f3