Colloids, Second Edition (1930)

By H. R. Kruyt

About this ebook

Colloids, Second Edition presents H. R. Kruyt's 1930 treatment of colloid chemistry, from classification and preparation to interfacial and electrical phenomena. Chemistry students and historical researchers can explore period explanations of suspensoids, emulsoids, stability, coagulation, and gelation, alongside the relationships between dispersed matter and its surrounding medium.

Inside this title

Historical classification, preparation, and purification of colloidal systems

$19.99~~Regular price $40.00~~Digital ebook

Buy now

Digital ebook. Checkout sends an order request.

Format: Digital ebook
Last updated: 2026-10-31

What this book covers.

Kruyt introduces colloidal systems by examining how they are classified, prepared, and distinguished from other forms of matter. Surfaces and interfaces provide a connecting theme, with adsorption, surface tension, and electrical behavior used to explain the properties of dispersed systems.

The second edition considers electrophoresis, electroosmosis, sedimentation, Brownian motion, coagulation, viscosity, and gel formation. Discussions of suspensoids and emulsoids preserve the terminology of the period, while preparation and purification methods include dialysis and ultrafiltration. Published in 1930, the textbook offers readers of physical chemistry and the history of science a way to study the conceptual organization of colloid research in the early twentieth century.

Study guide included

Inside Colloids, Second Edition (1930).

Kruyt's 1930 textbook introduces colloidal systems as a distinct form of dispersed matter, moving from classification and preparation into the interfacial and electrical behavior that explains their properties. Readers encounter the vocabulary and conceptual order of early twentieth-century colloid chemistry, preserved in its period terms and methods.

The book begins with how colloidal systems are classified, prepared and distinguished from other matter, including purification by dialysis and ultrafiltration. Surfaces and interfaces then become the connecting theme: adsorption, surface tension and electrical phenomena are used to account for the behavior of dispersed systems. Later discussion covers electrophoresis, electroosmosis, sedimentation, Brownian motion, coagulation, viscosity and gel formation, while the period categories of suspensoids and emulsoids organize the account. Because it was published in 1930, the text serves both students of physical chemistry and historians of science as a record of how colloid research was framed and taught before later developments reshaped the field.

Classification and preparation

The text opens by defining what makes a system colloidal and how such systems can be sorted into categories. Preparation methods are described as part of that definition, because how a colloid is made affects what it is. Purification by dialysis and ultrafiltration shows that the boundary between dispersed matter and medium must be controlled.

Colloidal systems are defined and classified
Preparation methods shape the product
Dialysis removes unwanted solutes
Ultrafiltration purifies dispersed systems

Topics 1–2

Surfaces and interfaces

Interfaces are the connecting theme of the book. Because colloidal particles expose a large surface relative to their volume, surface tension and adsorption govern much of their behavior. The text uses these interfacial concepts to explain phenomena that would otherwise seem disconnected.

Large surface area defines colloid behavior
Surface tension acts at interfaces
Adsorption concentrates matter at surfaces
Interfacial ideas unify the account

Topic 3–4

Electrical phenomena

Electrophoresis and electroosmosis are treated as evidence of electrical behavior at interfaces. The movement of particles in an electric field and the movement of liquid through a charged medium are described as related manifestations of the same underlying charge structure, central to the period's explanation of stability.

Particles migrate in an electric field
Liquid moves through charged media
Both reveal interfacial charge
Electrical behavior bears on stability

Topic 5

Suspensoids, emulsoids and period terms

The categories of suspensoid and emulsoid organize the book's treatment of dispersed systems. These are the terms of the period, and reading them on their own terms is part of understanding how colloid chemistry was then conceived. The distinction shapes which properties are emphasized for each type.

Suspensoids and emulsoids are distinguished
Period terminology frames the discussion
Each category highlights different properties
Categories reflect the era's understanding

Topics 7–8

Motion, coagulation and stability

Brownian motion and sedimentation describe how dispersed particles move, while coagulation describes how they come together and settle out. The text connects these observations to the question of why a colloid remains stable or destabilizes. Stability is explained through the interplay of motion, charge and interfacial forces.

Brownian motion keeps particles dispersed
Sedimentation reflects particle behavior
Coagulation destabilizes a system
Stability depends on competing forces

Topics 6–7

Viscosity and gel formation

Viscosity and gelation extend the account from dispersed particles to systems that thicken or set. Gel formation marks a change in the organization of the medium, and the book treats it as part of the same conceptual scheme rather than a separate topic. These properties connect laboratory observation to practical behavior.

Viscosity reflects internal structure
Gelation changes system organization
Gels belong to the same framework
Properties link to practical behavior

Topic 8

Topic map

Classifying Colloidal SystemsTopic 1
Preparation and Purification: Dialysis and UltrafiltrationTopic 2
Surfaces, Interfaces and Surface TensionTopic 3
AdsorptionTopic 4
Electrophoresis and ElectroosmosisTopic 5
Sedimentation and Brownian MotionTopic 6
Coagulation, Viscosity and StabilityTopic 7
Gelation and the Suspensoid/Emulsoid CategoriesTopic 8

Key takeaways

Read the suspensoid and emulsoid categories as period terms, not as modern classifications.
Follow the interfacial theme; surface tension, adsorption and charge explain most of the reported behavior.
Treat preparation and purification as part of what defines a colloidal system.

Students of physical chemistry and historians of science who want to study how colloid chemistry was organized and taught in the early twentieth century, including its period terminology, preparation methods and interfacial explanations.

Topics covered

colloid chemistry
colloidal systems
suspensoids and emulsoids
surface tension and adsorption
electrophoresis
electroosmosis
coagulation
gelation
history of chemistry

Questions about this ebook.

Edition, audience, and study-guide details at a glance.

What is Colloids, Second Edition (1930) about?

Which edition of Colloids, Second Edition (1930) is this?

This listing is for the 2nd edition. Check the title, ISBN, and book details above before ordering, especially if your course or reading list names a specific edition.

Who is Colloids, Second Edition (1930) for?

Does this page include a study guide?

Yes. This page includes an original study guide with six thematic sections, key takeaways, and a topic map for structured reading.