KOLOID PART 1 : PENGERTIAN, CONTOH & PERBEDAAN KOLOID DENGAN LARUTAN DAN SUSPENSI

Summary

The video explores the phenomenon of light scattering, particularly during sunset when sunlight creates visible rays through clouds. It introduces colloids as a type of mixture that falls between homogeneous and heterogeneous systems. Through examples, it explains the characteristics of solutions, colloids, and suspensions, highlighting their particle sizes, stability, and visibility. Solutions like sugar water are homogeneous, while mixtures like flour in water are heterogeneous. Colloids, such as milk, display unique properties, remaining stable and not easily separated. The video encourages viewers to identify these mixtures in everyday products.

Takeaways

• 🌅 Light scattering creates visible rays during sunset due to particles in the air.
• 💧 A colloid is a mixture that has properties between homogeneous and heterogeneous mixtures.
• 🍬 A solution, like sugar in water, is homogeneous, meaning its components cannot be distinguished even under a microscope.
• 🌾 A suspension, such as flour in water, is heterogeneous, with distinct layers that can settle over time.
• 🥛 When mixing water and instant milk powder, the resulting mixture is cloudy, indicating a colloidal system.
• 🔬 Colloids consist of a dispersed phase (like milk) and a dispersing medium (like water).
• ⚖️ Colloids appear homogeneous macroscopically but are heterogeneous at the microscopic level.
• 📏 Particle sizes in solutions are less than 1 nanometer, in colloids between 1 and 100 nanometers, and in suspensions greater than 100 nanometers.
• 🔄 Solutions are stable and do not separate, while colloids are stable but cannot be separated by regular filtration.
• ☕ Everyday examples of mixtures include solutions (like vinegar), colloids (like mayonnaise), and suspensions (like muddy water).

Q & A

What phenomenon is observed during sunset that relates to colloids?

During sunset, light rays penetrating clouds scatter due to colloidal particles in the air, creating visible rays of sunlight.

How are mixtures categorized in terms of their properties?

Mixtures are categorized into homogeneous mixtures, where components are uniformly distributed, and heterogeneous mixtures, where components remain distinct.

What distinguishes a colloid from a homogeneous mixture?

A colloid appears homogeneous to the naked eye but is heterogeneous when observed under ultra-microscopy, while a homogeneous mixture remains uniform at all observation levels.

What are the two phases that make up a colloid?

A colloid consists of a dispersed phase, which is the substance that is distributed (e.g., milk), and a dispersing medium, which is the substance in which the dispersed phase is distributed (e.g., water).

What are the size ranges of particles in solutions, colloids, and suspensions?

In solutions, particles are less than 1 nanometer; in colloids, they range from 1 to 100 nanometers; and in suspensions, they are greater than 100 nanometers.

How do the stability and separation methods differ among solutions, colloids, and suspensions?

Solutions are stable and cannot be separated by filtration, colloids are generally stable but can be separated using ultra-filters, while suspensions are unstable and can be easily separated by regular filtration.

Can you provide examples of colloids and suspensions?

Examples of colloids include milk, pudding, and mayonnaise, while examples of suspensions include mixtures like water and sand, coffee and water, and oil and water.

What happens to the components in a heterogeneous mixture over time?

In a heterogeneous mixture, components can settle or separate over time, as seen with flour in water, where the flour eventually sinks.

Why do colloids appear cloudy rather than clear?

Colloids appear cloudy because the dispersed particles scatter light, preventing it from passing through clearly, unlike a true solution that appears clear.

What is the significance of understanding colloids in everyday life?

Understanding colloids helps us recognize their presence in many everyday products, such as food items, cosmetics, and medicines, influencing their behavior and applications.