The density of NaOH solution is 1 . 2 g cm - 3 . The molality of this solution is m (Round off to the Nearest Integer): [Use : Atomic masses : Na : 23 . 0 u O : 16 . 0 u H : 1 . 0 u Density of H 2 O : 1 . 0 g cm - 3

Step-by-step solution

Consider 1 ℓ solution mass of solution = ( 1 . 2 × 1000 ) g = 1200   gm Neglecting volume of NaOH Mass of water = 1000   gm ⇒ Mass of NaOH = ( 1200 - 1000 ) gm = 200   gm ⇒ Moles of NaOH = 200   g 40   g / mol = 5   mol ⇒ molality = 5   mol 1   kg = 5   m