How much sodium chloride is needed to obtain 600 ml of its 0.5 molar solution?

Given:
V solution (NaCl) = 600 ml = 0.6 l
Cm (NaCl) = 0.5 M

To find:
m (NaCl) -?

Decision:
1) Calculate the amount of sodium chloride substance:
n (NaCl) = Cm (NaCl) * V solution (NaCl) = 0.5 * 0.6 = 0.3 mol;
2) Using the periodic system of D.I.Mendeleev, calculate the molar mass of sodium chloride:
M (NaCl) = Mr (NaCl) = Ar (Na) * N (Na) + Ar (Cl) * N (Cl) = 23 * 1 + 35.5 * 1 = 58.5 g / mol;
3) Calculate the mass of sodium chloride:
m (NaCl) = n (NaCl) * M (NaCl) = 0.3 * 58.5 = 17.6 g.

Answer: The mass of NaCl is 17.6 g.