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Differences Between Mixture and Compounds
1. Properties
- Mixture - Properties of the mixture are the same as the properties of the particles that make up the mixture. Remember, mixture are made via physical processes.
- Example: Kool-Aid is a mixture that is sweet from the sugar that makes it up (which is also sweet). Is that not why we drink Kool-Aid anyway for the "sugar high".
- Compound - At least one of the compounds properties is different than the particles that make it up.
- Example: Solid table salt (called Sodium chloride) is composed from solid elemental sodium metal and gaseous (a green color) elemental chlorine.
2. Separation Techniques
- Mixtures - physical separation of base units or particles (simply moving particles closer or farther away from each other, not changing particles)
- Example: filtering, boiling (phase change), spinning (machine is called centrifuge).
- Called physical change
- Compound - chemical reactions, you are changing the particles (changing which atoms are grouped together via moving of valence electrons)
- Example: Rusting
- Called a Chemical change (all chemical changes are chemical reactions - atoms or particles have regrouped (new grouping called products, old grouping called reactants) via changing how atoms deal with valence electrons)
3. Composition (Proportions) - how many or ratio of each particle are there in the material.
- Mixture - variable either in the same container and/or between containers
- Heterogeneous mixture - variable both in the same container and between contanier.
- Homogenous mixture - variable between containers but SAME in same container.
- Compounds - always same composition either in the same container or between containers.
- Definition of Compound: 2 or more atoms chemical combined in a fixed mass ratio.
Note: As stated above, homogeneous mixture and compounds must have same composition thru the container, why are they not same thing (can't use properties or separation techniques to explain). Answer is that homogeneous mixture do not have to be the composition between container but compounds do always have same composition in container or between container (remember definition of compound).