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What is the molality of a solution made by mixing 15 grams of Ba(OH)2 in 250 grams of water?

User Rxdazn
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1 Answer

2 votes

Answer:

The answer to your question is molality = 0.35

Step-by-step 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

User Mats Wichmann
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