Which element combination(s) would result in a transfer of electrons?
sodium (na) and chlorine (cl)
nitrogen (n) and oxygen (o)
aluminum (al) and fluorine (f)
sodium (na) and calcium (ca)

The graph above shows how the price of cell phones varies with the demand quantity. the equilibrium price for cell phones is where both supply and demand quantities equal $100, 5,000 5,000, $100

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)

How is an endothermic reaction identified