Answer:
1.47 m
Step-by-step explanation:
The molality can be found using the following equation:
Molality = moles solute / mass (kg) solvent
In this case, NaCl is the solute and H₂O is the solvent. To find the molality, you need to (1) convert grams NaCl to moles (via the molar mass), then (2) convert grams H₂O to kilograms, and then (3) calculate the molality.
(Step 1)
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
30 grams NaCl 1 mole
-------------------------- x ------------------------ = 0.513 moles NaCl
58.443 grams
(Step 2)
1,000 grams = 1 kg
350 grams H₂O 1 kg
-------------------------- x ----------------------- = 0.35 kg H₂O
1,000 grams
(Step 3)
Molality = moles solute / mass (kg) solvent
Molality = 0.513 moles NaCl / 0.35 kg H₂O
Molality = 1.47 m