Jawabanmu

2014-08-03T18:26:12+07:00
Elektron = 2 + 8 + 8 = 18 . Neutron = 22, jadi No.massa = Neutron + Elektron = 22+18 =40
1 4 1
2014-08-03T18:32:14+07:00
Nomor Massa Atom = Proton + Neutron
No. Massa = (2+8+8) + 22
No. Massa Atom = 40

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