common questions asked to the companies (flipkart) regarding global issues
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When water soluble substances like sodium chloride, copper sulphate, sugar etc. are put into water, they dissolve and a homogeneous solution is obtained. The particles of the solute are not visible and their size is molecular size. Such mixtures are called molecular solutions or true solutions. Now suppose, we take muddy river water or an insoluble substance like lead sulphate or calcium sulphate is put into water. The particles of the solutes are visible even with the naked eye because their size is large. On keeping for some time, particles settle down. These mixtures are called suspension. In between these two extremes, there are particles which are bigger than molecules but are too small to be seen even by a microscope.
The colloidal state can thus, be regarded as the intermediate state between molecules and particles of a coarse suspension.