How many grams of a 1000-gram radioactive sample are left after 3 half-lives? 1000 grams 500 grams 250 grams 125 grams 2000 grams

Mrs. smith ordered a root beer float (vanilla ice cream + root beer). mrs. smith noticed that the three states of matter (solid, liquid, and gas) all existed simultaneously in her root beer float. a. identify each phase of matter in the root beer float. b. describe the particles of all three phases of matter in the root beer float. (how are the particles arranged and moving? ) c. identify one phase change you would see in a root beer float and described what causes this change.

Why do scientists look for patterns in the world? a. patterns can explain observations. b. patterns never change, no matter what. c. patterns are easy for scientists to detect. d. patterns are all the same, through all time.

Which best describes why nh4+ can form an ionic bond with ci-?