Which of these elements is the least reactive? A.
sodium

B.
krypton

C.
chlorine

D.
aluminum

When sodium chloride dissolves in water, the sodium chloride dissociates into a. na- ions. b. cl+ ions. c. nacl ions. d. sodium chloride ions.

In the 1500s, an astronomer developed a new model of the universe. this model had the sun at the center of the universe, not earth. who was this astronomer?

If you see a sedimentary outcrop and red layers of sand are at the top of pale layers of rock, what does this tell you about the ages of the rock layers?