The molarity of a saline solution that contain 0.900 g NaCl (58.44 g/mol) dissolved in 100.0 ml solution is 0.15 M
calculation
Molarity = moles /volume in liters
volume in liters = 100.0 ml / 1000 = 0.1 L
moles = mass÷ molar mass
= 0.900 g ÷58.44 g/mol =0.015 moles
molarity is therefore = 0.015 moles / 0.1 L =0.15 M