Density of 3 M NaCl solution is 1.25 g/mL. The molality of the solution is :
- 2.79 m
- 2 m
- 1.79 m
- 3 m
Answer
(1) 2.79 m
Solution
Take 1 L: mass of solution =1250 g, NaCl =3 58.5=175.5 g
⇒ water =1074.5 g =1.0745 kg
∴ m= 31.0745=2.79 m
Answer: (1)
Density of 3 M NaCl solution is 1.25 g/mL. The molality of the solution is :
(1) 2.79 m
Take 1 L: mass of solution =1250 g, NaCl =3 58.5=175.5 g
⇒ water =1074.5 g =1.0745 kg
∴ m= 31.0745=2.79 m
Answer: (1)
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