Print | Recommend This Site

Heterogeneous Mixture

A mixture where two or more substances are mixed together but are not chemically combined is called as an heterogeneous mixture...

Last Updated On: Tuesday, June 29, 2010

 
 

When two or more substances are combined together but not in any particular or fixed proportion then it is called as a mixture. A mixture can be classified into two categories - homogeneous mixture and heterogeneous mixture. A mixture that has a same composition throughout with uniform appearance is called as homogeneous mixture. A homogeneous mixture is also known as a solution. A heterogeneous mixture on the other hand is made of more than one phase and can be separated physically. They also do not have a uniform composition throughout the mixture.

Heterogeneous Mixture Explained
Suspensions and emulsions are two special types of heterogeneous mixture. A suspension is a mixture of solids and liquid in which the solids do not dissolve in the liquid solution. When a suspension is allowed to stand for some time and left undisturbed, the solid particles settle at bottom of the container. An example of suspension is sand in water and clay in water. An emulsion is a special type of suspension where a mixture consists of two liquids which do not mix together. When two such liquids are kept together they do not mix, no matter how much you try to do so by shaking or stirring. They will ultimately settle into two layers one above the other when left undisturbed for considerable period of time. Examples of emulsions are kerosene and water and a mixture of oil and water. Both suspensions and emulsions show the Tyndall effect.

The definition of a heterogeneous mixture is one which does not have a uniform composition and has visible sharp boundaries. Heterogeneous mixture are those in which the substances are not distributed evenly. They usually involve a mixture of a solid in a solid. The main difference between solutions and mixture is that a solution can only be separated into its original components by chemical means whereas a mixture can be separated by mechanical means. For example, if you mix sugar granules in a glass of water, the sugar granules completely dissolves in the water. This sugar solution is an example of homogeneous mixture. Now if you want to separate the sugar crystals from the sugar solution it is not possible to do so by mechanical means. For this you have to first boil the sugar solution so that all the water evaporates into the air and the sugar crystals will be left behind.

Now let us take the example of a mixture. If you have a heterogeneous mixture of two substances say, sand and iron fillings then you can easily separate them by mechanical means. This can be done by using a magnet to sift the iron fillings away. All you will be left behind is the sand. Thus a simple mixture can be separated by mechanical means. Some other mechanical means by which a mixture can be separated are sifting, filtration and by using gravity.

Heterogeneous Mixture Examples
Now that we have answered the question as to what is heterogeneous mixture in chemistry, let us list some examples of heterogeneous mixture.
Sand in water
Smoke
Blood
Chicken soup
Protoplasm
Silt in water
Tomato juice
Clouds
Vinegar in oil
Air
Mayonnaise
Ice tea
Concrete
Wood
Oil paint
Hand cream
Salad dressing
Soil
Chocolate chip cookie
Muddy water
sugar and cornstarch
Salt and iron fillings
Salt and Sugar mixture
Mixture of different types of cereals
Mixture of stones in soil
Trail mix
Lentil soup
Peanut butter
Aerosol spray

So this was all about heterogeneous mixture and how they can separated into their individual components. The most important thing to remember is that heterogeneous mixture consists of visibly different phases and substances and they are never chemically combined.

 

Homogeneous Mixture, Heterogeneous Mixture, Uniform Appearance, Suspensions, Emulsions, Mixture of Solids and Liquid, Liquid Solution, Tyndall Effect, Protoplasm, Mayonnaise, Salt and Sugar Mixture, Lentil Soup, Aerosol Spray