Identify the appropriate reagent (A-H) you would use to accomplish the given transformation. A. MeONa B. H2, Pt C. t-BuOK D. 1) Hg(OAc)2, H2O; 2) NaBH4 E. HBr F. HBr, ROOR G. HCl H. 1) BH3-THF; 2) H2O2, NaOH

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.