A toothpaste contains 0

Please see the attached file.

A toothpaste tube contains 0.24% by mass of sodium fluoride used to prevent caries (cavities) and 0.30% by mass of triclosan (C12H7Cl3O2).

a) How many moles of NaF are in a tube of toothpaste?
Mass of NaF = 0.24*119/100 = 0.2856 g
Molecular weight of NaF = 23+19 = 42 grams/mol
Number of moles of NaF present in a tube of toothpaste = 0.2856/42 = 0.0068

b) How many moles of F- are in a tube?
1 mol of NaF would contain 1 mol of F-.
Number of moles of F- present in a tube of toothpaste = 0.0068

c) How many grams of Na+ are in 1.50g of toothpaste?
1 mol of NaF would contain 1 mol of Na+
Number of moles of Na+ present in 119 grams = 0.0068
Therefore, number of moles of Na+ present in 1.5 grams = 1.5*0.0068/119
= 0.0000857

d) How many molecules of triclosan are in a tube of toothpaste?
Mass of triclosan = 0.3*119/100 = 0.357 g
Molecular weight of triclosan = 12*12+7*1+3*35.5+2*16 = 289.5 grams/mol
Therefore, number of moles of triclosan present in a tube of toothpaste
= 0.357/289.5 = 0.001233