Why is milk a stable colloid?

Answer 1

A colloid is a mixture that consists of charged (usually negatively) particles that repel each other making it so that they don't collect and separate.

Even though milk appears to be a homogeneous mixture, it is a colloid because it has small globules of fat and protein that do not settle out after standing due to the particles (usually negatively) charged particles. These particles repel each other so they do not collect into larger particles that would settle out.

However, if you were to add acid to milk, the acid would neutralize the charge and the particles would coagulate and settle to the bottom of the container.

so: Milk is a colloid because it has small globules of fat and protein that do not settle out (due to their negative charges that repel each other).

Hope I helped

-M

Answer 2

Because it is not a solution. It's particles can be seen when you put light in it.
Milk contains a series of lipid globules surrounded by an outer coating in a proteinous structure called a micelle. This micelle shields the lipids from separation by providing an electronegative and consequently hydrophilic covering around the lipids. The electronegativity also prevents the micelles from sticking together and forming large grains. However, these micelles are still reasonably-large particles which are not dissolved in the surrounding water, so the substance is a colloid.

Answer 3

A colloid is defined as a combination of a continuous phase and a discontinuous phase in which the particles of the discontinuous phase are large enough to scatter light but not large enough to spontaneously separate from the continuous phase under normal conditions. Milk fits this definition: It is a suspension of fat particles in a continuous phase called "whey". A transparent container of milk is opaque because the fat particles scatter light that would otherwise pass through the milk, but the fat particles do not separate spontaneously from the whey very quickly unless the milk is "churned" (strongly agitated).

Answer 4

Milk that you buy from the store is a stable colloid because it has been homogenized. Homogenized milk has the fat broken into small enough pieces that they remain stable in solution. Raw milk is not stable and quickly separates into milk and cream.

Answer 5

an emulsified colloid

Answer 6

Yes