test #1 notes – con’t concept map #2 classification of matter
TRANSCRIPT
Test #1 Notes – Con’t
Concept Map #2
Classification of Matter
The Phases (States) of Matter1. Solid (s) * definite shape & definite volume * particles are in a regular, geometric pattern or crystalline shape * particles vibrate in fixed positions
2. Liquid (l) * take shape of container, definite volume * particles can flow
3. Gas (g) * expand to completely fill container * no definite shape or volume
Note - Vapor refers to a substance that is not normally a gas.
(aq) = Aqueous = the substance is dissolved in water.
http://www.youtube.com/watch?v=s-KvoVzukHo&feature=related
4. The phases differ due to differences in the: a) arrangement or distance between their particles b) attraction between their particles.
Phases – con’t
Solid Liquid Gas
The Three Classes of Matter:Elements
Compounds Mixtures
Matter
Substance Mixtures of Substances (fixed composition) (composition varies)
Elements Compounds Heterogeneous Homogeneous
(these are homogeneous) Suspensions Solutions
Models
1. Elements (made of a single kind of atom)
Monatomic Element or Diatomic Element
He H2
2. Compounds (hook different atoms together to show they are chemically combined)
Water is a compound (H2O)
3. Mixtures (the different substances aren’t hooked – shows they are physically combined)
Mixture of Water (H2O) & Oxygen (O2)
Elements
1. Elements are substances composed of atoms that cannot be broken down any further.2. A particular element contains atoms having the
same atomic number.3. Some examples: Iron (Fe) or Hydrogen (H2)
Elements – con’t
4. Some elements exist in several different forms. They have different structures & different properties. (Allotropes) Example: Forms of solid Carbon
Elements – con’t
Example: Forms of Oxygen gas
Most oxygen in the air is O2. This is the odorless gas that sustains life.
Ozone is O3. Ozone gas has a sharp odor and damages respiratory tissue.
Compounds
1. Compounds are substances composed of atoms from 2 or more different elements chemically combined in a fixed or definite ratio.
2. The compound’s properties are not the same as its component’s original properties.
Examples: Water (H2O)
Sodium Chloride (NaCl)
Mixtures
1. Mixtures are composed of 2 or more different substances physically combined in any ratio.
2. The composition of a mixture is not fixed. For example grape juice may be really sweet or tart.
3. The components of a mixture keep (or retain) their original individual properties.
Examples: Raisin Bran, Chex Mix, Koolaid, Italian Salad Dressing
E, C, or M?
1. NH3(g)
2. Br2(l)
3. H2SO4(aq)
4. Cu(s)5. NaCl(s)6. NaCl(aq)
Answers: C, E, M, E, C, M
Homogeneous Mixtures
You cannot see the different parts because the particles are uniformly or evenly mixed resulting in constant properties throughout that sample.
Examples: Kool-Aid, Air, Milk, Saltwater.
Heterogeneous Mixture
You can see visibly different parts because the particles are NOT uniformly mixed.
Examples: Soil, Vegetable soup, Trail mix,
Lucky charms
Miscible vs Immiscible
1. Miscible refers to mixtures of liquids that dissolve in each other
Example: water & vinegar
2. Immiscible refers to mixtures of liquids that separate (don’t dissolve)
Example: water & oil
Solutions1. A solution is a homogeneous mixture containing a solute
dissolved in a solvent. Example: sugar water C12H22O11 (aq)
(aq) = aqueous = dissolved in water
2. The solute (sugar) is the substance dissolved.
3. The solvent (water) does the dissolving.
4. They cannot be separated by filtration.
Note: If a solid dissolves, we say it is soluble.
Suspensions
1. A suspension is a heterogeneous mixture of an insoluble solid suspended in a liquid.
2. The insoluble solid doesn’t dissolve, it will settle on standing.
3. An example is cornstarch mixed in water.4. They can be separated by filtration.
Separation of Mixtures
1. The components in a mixtures can be separated physically - based on differences in properties such as color, density, solubility, etc.
2. Some examples: (see pictures) Filtration (particle size) Chromatography (absorption) Distillation (boiling point)
Filtration
In filtration, larger solid particles are separated from smaller liquid particles by passing the mixture through a filter.
http://www.youtube.com/watch?v=P6yhfd2i0cw&feature=relmfu
Distillation
Distillation uses differences in the boiling points to separate a homogeneous mixture into its components.
http://www.youtube.com/watch?v=xxNfJLMNS4E
Chromatography
Separation of components of black ink
http://www.youtube.com/watch?v=08YMBGS1pYU
Chromatography separates substances in a mixture based on differences in absorption up a strip of paper dipped in a solvent.
Separation of Compounds
Occurs only by chemical reaction
Example: Decomposition of water into hydrogen and oxygen gas
http://www.youtube.com/watch?v=EE58a5fN468