Lời giải:Đáp án B
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{n_{C{l_2}}} = {\rm{ }}4,48{\rm{ }}:{\rm{ }}22,4{\rm{ }} = {\rm{ }}0,2{\rm{ }}mol\)
2RCl → 2R + Cl2
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{n_R} = {n_{C{l^ - }}} = {n_{RCl}} = 2{n_{C{l_2}}} = {\rm{ }}0,4{\rm{ }}mol\)
→ MRCl = 23,4 : 0,4 = 58,5 (g/mol)
→ MR = 58,5 – 35,5 = 23 (g/mol) (Na)
