... 100 38 0, 06 100 XA 99,6 100 ! 39,98 21 XA = 40 m 1.16 Hng dn: c o Ta cú a) Nguyờn t trung bỡnh ca Mg l A Mg ! 24 78,6 10, 1 11,3 25 26 ! 24,33 100 100 100 50 x78,6 = 389 (nguyờn t) 10, 1 ... AAg = 107 ,02 A H m A H = M H2 = 1,0079 AAg = 107 ,02 1,0079 = 107 ,865 s 1.9 Hng dn: h a) Nguyờn t trung bỡnh ca hiro v clo l: 35.75,53 37.24,47 = 35,5 100 a t 1.99,984 2.0,016 ! 1,00016 100 ... tớch: qe = -1,602 .10- 19C = 1- w v - Khi lng: me = 9 ,109 5 .10- 31 kg Ht nhõn: Bao gm cỏc proton v cỏc ntron a Proton - in tớch: qp = +1,602 .10- 19C = 1+ w - Khi lng: mp = 1,6726 .10- 27 kg } 1u (vC)...