Clutch Prep is now a part of Pearson
All Chapters
Ch.1 Matter and Measurements
Ch.2 Atoms and the Periodic Table
Ch.3 Ionic Compounds
Ch.4 Molecular Compounds
Ch.5 Classification & Balancing of Chemical Reactions
Ch.6 Chemical Reactions & Quantities
Ch.7 Energy, Rate and Equilibrium
Ch.8 Gases, Liquids and Solids
Ch.9 Solutions
Ch.10 Acids and Bases
Ch.11 Nuclear Chemistry
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Solubility and Intermolecular Forces
Solutions: Mass Percent
Percent Concentrations
Parts per Million (ppm)
Solubility: Temperature Effect
Intro to Henry's Law
Henry's Law Calculations
Solution Stoichiometry
Electrolytes (Simplified)
The Colligative Properties
Boiling Point Elevation
Freezing Point Depression
Osmotic Pressure

Molality (m) represents the amount of solute dissolved per kilogram of solvent. 

Understanding Molality

Example #1:

Molality is depicted as moles of solute per kilograms of solvent.


Concept #1: Ionic molality or osmolality represents the molality of dissolved ions in a solution. 


Example #2:

A solution is prepared by dissolving 43.0 g potassium chlorate, KClO3, in enough water to make 100.0 mL of solution. If the density of the solution is 1.760 g/mL, what is the molality of KClO3 in the solution? MW of KClO3 is 122.55 g/mol. 

Molality Calculations

Example #3:

If the molality of glucose, C6H12O6, in an aqueous solution is 2.56 what is the molarity? Density of the solution is 1.530 g/mL.


Example #4:

What is the ionic molality of nitrate ions in 0.305 m lead (IV) nitrate, Pb(NO3)4?.


Practice: What is the mass percent of NH3 of a 1.25 m aqueous solution of NH3?