a) \({M_{Cl}} = 35,5\,g/mol;\) \({M_{C{l_2}}} = 35,5.2 = 71\,g/mol\).
b) \({M_{Cu}} = 64\,g/mol;\) \({M_{CuO}} = 64.1 + 16.1 = 80\,g/mol\).
c) \({M_C} = 12\,g/mol;\) \({M_{CO}} = 12.1 + 16.1 = 28\,g/mol;\)\({M_{C{O_2}}} = 12.1 + 16.2 = 44\,g/mol\).
d) \({M_{NaCl}} = 23.1 + 35,5.1 = 58,5\,g/mol;\)\({M_{{C_{12}}{H_{22}}{O_{11}}}} = 12.12 + 1.22 + 16.11 \)\(= 342\,g/mol\).