Why are mass numbers more than atomic mass
XIAO Hai-guang Jinzhong Teacher's College, Shanxi 030600 China
Mass numbers and atomic mass are fundemental concept in secondary chemisery. The former represents the sum of some certain unclern atomic nueleus and its neutron numbers;the latter represents the mass of some certain nuclein. It is of significance to the relative size be-tween the two in learning chcmical knowledge.
【CateGory Index】： G633.7