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Differences Between Mixture and Compounds
1. Properties - observations of the material (in lab we call it observations)
- Physical property - observation when base unit or particles do not change.
- Example: Density, length, mass, phase (also called state) of matter, etc.
- Chemical property - observation when base unit or particles do change (name we give observation of chemical reactions)
- Example: rusting, flammability
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).