Answer:
The answer to your question is molality = 0.35
Explanation:
Data
Molality = ?
mass of Ba(OH)₂ = 15 g
mass of water = 250 g
Process
1.- Calculate the molar mass of Ba(OH)₂
Ba(OH)₂ = 137 + 32 + 2 = 171 g
2.- Convert the mass to moles
171 g ------------------ 1 mol
15 g ---------------- x
x = (15 x 1) / 171
x = 15/171
x = 0.088 moles of Ba(OH)₂
3.- Calculate molality
Formula
molality = moles/mass of solvent (kg)
Substitution
molality = 0.088 / 0.250
Result
molality = 0.35
