You are working in your laboratory and decide to do some cleaning. you find a test tube with some brown substance congealed at the bottom. you take a piece of iron wool to scrub it out, but cannot remove it. you leave the iron wool in the test tube and set it aside to clean your beakers instead. you do not realize the test tube is next to the heater and after a few minutes, a brown gas starts smoking out of the test tube, followed by a reddish-brown gas. upon observation, the iron wool is coated in a yellow-brown substance. you realize that the mystery substance was
a. bromine (br) b. iodide (i) c. argon (ar) d. scandium (sc)

1. why does the same side of the moon always face earthc.the rotational period of the moon is equal to one revolution around earth2. which is greater the moons period of rotation or its period of revolution  b.the moons revolution period around earth3.what was the major accomplishment of the apollo missions  c.sending the first human into space4. which of these space missions involved the deployment of lunar roversa. voyager 15. which scientists are going to explore next on kepler-186fd. evidence of existence of life6.which mission is not going to explore the outside of the solar  systemb.safir7.which technology limit the future of space explorationb. scientist must first develop certain technologies before missions can be completed.

It would be c. risk.