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Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.

Name the element in group 17, period 2. (periodic table)

Consider the following multistep reaction: a b→ab(slow) a ab→a2b(fast)−−−−−−−−−−−−−−−−− 2a b→a2b(overall) based on this mechanism, determine the rate law for the overall reaction. express your answer in standard masteringchemistry format. for example, if the rate law is k[a]3[b]2 type k*[a]^3*[b]^2