The nuclide nb decays by beta emission with a half-life of 1.23 hours. the mass of a 97nb atom is 96.908 u. (a) how many grams of "'nb are in a sample that has a decay rate from that nuclide of 456 sl? (b) after 5.04 hours, how many grams of %7nb remain?

3.09 lab: reaction of metals 1 which combinations of substances resulted in a chemical change? for each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. make a general statement about the reactivity of the metals in this experiment.