The size of colloids is :  1 point1 to 10000 nm10 to 100 nm1 to 1000 nm1 to 100 nm

Step 1: Break Down the Problem

We need to identify the correct size range that defines colloids from the provided options.

Step 2: Relevant Concepts

Colloids are defined as mixtures where microscopically dispersed insoluble particles are suspended throughout another substance. The size range of colloidal particles typically falls between 1 nanometer (nm) to 1 micrometer (µm), which is equivalent to 1000 nanometers.

Step 3: Analysis and Detail

Let's evaluate the provided options:

1. 1 to 10000 nm: This range is very broad and includes sizes beyond the typical colloidal range.
2. 10 to 100 nm: This range falls within the colloidal size range but is too narrow.
3. 1 to 1000 nm: This range includes all particles classified as colloids (1 nm to 1000 nm).
4. 1 to 100 nm: This range is also inside the colloidal size range but is too narrow.

Step 4: Verify and Summarize

Based on the pertinent definitions and evaluations, the most accurate size range that encompasses colloidal particles is from 1 to 1000 nm.

Final Answer

1 to 1000 nm is the correct size range for colloids.