What is electronic confriguration

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.

As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit

Identify the lewis acid in this balanced equation: ag+ + 2nh3 -> ag(nh3)2+a. ag+b. nh3c. ag(nh3)2+