【单选题】The atomic masses of its two stable isotopes 29 63 Cu(69.09 percent) and 29 65 Cu(30.91 percent) are 62.93 amu and .9278 amu, respectively.calculate the average atomic mass of copper.
【单选题】Boron has two naturally occurring isotopes, 10B with an atomic mass of 10.0129370 amu and 11B with an atomic mass of 11.0093054 amu. The atomic mass of boron is 10.81 (from the periodic table). The pe...