Video Transcript
Order the following mixtures according to the size of the particles found in them from smallest to largest. Suspensions, colloids, solutions.
In order to answer this question, let’s start by discussing some of the properties of each of these types of mixtures. Suspensions are heterogeneous mixtures, meaning they have an uneven composition. To envision a suspension, you might think of a shaken snow globe. In this example, particles may be distributed evenly for a period of time. Over time, however, the particles will settle to the bottom of the container. Suspensions, therefore, are mixtures with relatively large particles. And the particle size tends to be greater than or equal to 1000 nanometers in diameter.
Next, colloids are mixtures that appear homogeneous to the naked eye. However, at the microscopic level, colloids are often heterogeneous in composition. And particles in colloids tend to range between one and 1000 nanometers.
And finally, we have solutions. Solutions are homogeneous mixtures, meaning that any region of the solution that we look at will have the same composition as any other. One example of a solution would be when you add sodium chloride, or table salt, to water. In this example, the particles that make up the sodium chloride are completely solvated by the water molecules, creating free ions in solution. In solutions, particles range in size from 0.01 to one nanometer. Particles this small can neither be seen by the naked eye or by a standard light microscope.
With this information in hand, we can now order the following mixtures according to the size of the particles found in them from smallest to largest. And the correct answer is solutions, which have the smallest particles, than colloids, than suspensions, which have the largest particles.
