Answer: All the points apply for colloids.
Explanation: This question can be answered only by looking at the properties of colloids:
- The particle size of these systems range from 1nm to 1mm.
- These are generally considered as heterogeneous mixtures but have some properties of homogeneous mixtures. There is some physical boundary present between solute and solvent.
- These solutions cannot be separated by ordinary filtration.
- Tyndall effect: This effect is generally seen in colloidal solutions or solutions having very fine suspension. This effect is basically the scattering of light by the particles. This effect can be seen in the sky when sunlight is scattered by clouds.
- These solutions have small particle size thus it cannot be seen from bare eyes, thus we need optical microscope.
- Cloud, Milk, Fog and Smoke are some of the examples of Colloidal solutions.
These properties enlisted above show that all the points given in the question are correct for colloidal solutions.
That answer is up to your knowledge
Answer:
I think
a. iron oxide with Aluminium
