Difference between Compound and Mixture
By Theydiffer - May 14, 2016

Chemistry isn’t actually an easy subject to learn, simply because of the many compounds and mixtures involved within atoms and elements. If you think that both mean the same thing, you may want to read on.

Definitions

Compound

Getty Images/Moment/Stefania Pelfini, La Waziya Photography

A compound is an entity that consists of two or more atoms from at least two different elements and involves chemical bonds (a lasting attraction between atoms). In other words, it is a chemical union between separate elements, ingredients, or parts. With the way these atoms are held together, they do not retain their individual properties.

Types of Compounds

  1. Covalent bonds – A chemical bond that requires sharing of electron pairs (two electrons that occupy the same orbital but have opposite spins) between atoms. An example of this compound is the ever famous H2O (water).
  2. Ionic bonds – A chemical bond that requires the electrostatic attraction between ions (atoms that have lost one or more electrons, and atoms that have gained one or more electrons) that are oppositely charged. A sample of this compound would be table salt.
  3. Inter-metallic compounds – This bond is a solid-state compound that exhibits metallic bonding. These compounds are often simply called alloys (mixture of metals or a metal with another element).
  4. Coordinate bonds – A bit more complicated than the other three, it is a compound that is a kind of 2-center, 2-electron covalent bond, and in which the two electrons are derived from the same atom. A sample of this compound is mixing ammonia (NH3) and hydrochloric acid (HCL), forming a thick white smoke of ammonium chloride.

Mixture

In chemistry, a mixture is made by combining two or more different substances into one, but they are not chemically combined. It means the combination of these substances may only result in a physical combination, and thus the identities of each substance is retained. That being said, a mixture does not form a new substance, and can also be separated by physical methods.

Types of Mixtures

  1. Homogeneous – It is a mixture with uniform composition, meaning components are uniformly distributed throughout the mixture. Also, particles have the same properties.  A good example of this would be sugar water.
  2. Heterogeneous – It is a mixture in which components have a non-uniform composition and can be seen. Cereal mixed with milk is one example.

Compound vs Mixture

What’s the difference between compound and mixture? They may have the same concept, but they operate in their own different ways.

Starting with compounds, these are substances that are combined to form new substances that show no signs of their previous properties. The product has different chemical properties and will always contain the same ratio of its component atoms. Take two molecules of hydrogen and a single molecule of oxygen for example. When combined, they no longer have their own chemical properties, and will always require the ratio of 2:1 (hydrogen: oxygen).

A mixture, on the other hand, involves only the physical combination of these substances. Unlike compounds, they can be combined in any ratio. Also, each of these substances has their own chemical properties.

One other difference would be the means of separating these combined substances. Compounds can be broken down into their elements, but only by chemical means. Mixtures however, can be separated through physical means.

Comparison Chart

CompoundMixture
Combination of elements with chemical reactionCombination of ingredients achieved physically
Can only be separated through chemical meansCan be separated through physical means
Ingredients do not retain their chemical propertiesIngredients retain their chemical properties
Pure substancesImpure substances
New substance is formedNo new substance is formed
Compositions are fixedCompositions are variable