Sodium an alkali metal and chlorine a halogen are both in period 3? of the periodic table. which element has a higher ionization energy? explain

Brainliesttt me asap! the below reaction can be categorized as more than one type of reaction. which reactions are these, and what are the types of reactions?

Agas can holds 2.0 gal of gasoline. what is this quantity in cubic centimeters?

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)