Answer
0.50 mol $Cl_{2}$ posses the greatest mass.
Work Step by Step
a) 5.0 g $Cl_{2}$
b) Molar mass of $NaClO_{3}$ = 106.44 g/mol
106.44 g $NaClO_{3}$ contains 35.5 g $Cl$
So mass of Cl in 60.0 g = $35.5\times60.0\div106.44$ = 20.0 g
c) Molar mass of $KCl$ = 74.55 g/mol
Mass in grams = Number of moles $\times$Molar mass
Mass of $KCl$ = $0.10\times74.55 = 7.46 g$
74.55 g $KCl$ contains 35.5 g $Cl$
So mass of Cl in 7.46 g = $35.5\times7.46\div74.55$ = 3.6 g
d)Molar mass of $MgCl_{2}$ = 95.21 g/mol
95.21 g $MgCl_{2}$ contains 71.0 g $Cl$
So mass of Cl in 30.0 g = $71.0\times30.0\div95.21$ = 22.3 g
e) Molar mass of $Cl_{2}$ = 71.0 g/mol
That is 1 mol $Cl_{2}$ = 71.0 g
So 0.5 mol $Cl_{2} = 71.0 g \times 0.50 = 35.5 g$
Thus, 0.50 mol $Cl_{2}$ posses the greatest mass.
