1 properties chapter 3. 2 chemical vs physical properties a chemical property the ability or...
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Properties
Chapter 3
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Chemical vs Physical Properties
A chemical property the ability or inability of a substance to combine with or change into one or more new substances
A physical property is a characteristic of matter that can be observed or measured without changing the sample's composition—for example, density, color, taste, hardness, and melting point
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chemical properties
physical properties
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Intensive vs Extensive
Intensive property: a physical property that remains the same no matter how much a substance is present
Extensive property: a physical property, such as mass, length, and volume, that is dependent upon the amount of substance present
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chemical properties
physical properties
Intensive Extensive
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chemical properties
physical properties
Intensive Extensive
Qualitative Quantitative Qualitative
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Chemical vs Physical Changes
Chemical change - a process involving one or more substances changing into new substances; also called a chemical reaction
Physical change - a transition of matter from one state to another
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Which of the following are chemical changes? Select all that apply.
1. breaking glass
2. building a birdhouse
3. rusting bicycle
4. melting butter
5. spoiling food
6. mixing lemonade
7. mowing the lawn.
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Which of the following are chemical changes? Select all that apply.
1. breaking glass
2. building a birdhouse
3. rusting bicycle
4. melting butter
5. spoiling food
6. mixing lemonade
7. mowing the lawn.
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Which of the following are physical changes? Select all that apply.
1. corroding metal
2. bleaching hair
3. fireworks exploding
4. squeezing oranges to make OJ
5. frying an egg
6. making salt water to gargle your sore throat.
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Which of the following are physical changes? Select all that apply.
1. corroding metal
2. bleaching hair
3. fireworks exploding
4. squeezing oranges to make OJ
5. frying an egg
6. making salt water to gargle your sore throat.
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Which properties below are extensive qualitative, physical properties?
1. yellow
2. hot
3. heavy
4. explosive
5. long
6. hard
7. very dense
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Which properties below are extensive qualitative, physical properties?
1. yellow
2. hot
3. heavy
4. explosive
5. long
6. hard
7. very dense
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Which properties below are intensive quantitative, physical properties?
1. 35ºC
2. 26.2 g
3. 3.7 cm
4. 2.5 g/ml
5. 85 miles/hour
6. 450 ml
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Which properties below are intensive quantitative, physical properties?
1. 35ºC
2. 26.2 g
3. 3.7 cm
4. 2.5 g/ml
5. 85 miles/hour
6. 450 ml
Chapter 3
Matter matters.
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Water, it’s an amazing substance
• Earth is the only place in the universe that we know of that has the right conditions for water to exist as solid, liquid, and gas in the same place at the same time.
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Select the statement(s) below that gives the best nanoscopic explanation as to why solids are rigid (hard).
1. the particles are very small.
2. the particles are stuck together.
3. the particles are touching each other.
4. the particles are aligned in a regular and repeating pattern.
5. the particles are polar, so they are “sticky”
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Select the statement(s) below that gives the best nanoscopic explanation as to why solids are rigid (hard).
1. the particles are very small.2. the particles are stuck together.3. the particles are touching each other.
Of course to be stuck, the particles would need to be touching, but it is not the act of touching that makes them rigid.
4. the particles are aligned in a regular and repeating pattern.
While choice #2 is the best response, it does make sense that for any substance to be regular and repeating, the particles would need to be stuck to one another, but not all solids are arranged in a repeating pattern. Yet in all solids, the particles must be stuck together.
5. the particles are polar, so they are “sticky”
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Explaining the Macroscopic by Describing the Nanoscopic
Solid Liquid Gas
Macroscopic property: Compressible or not? NOT compressible compressible
Nanoscopic explanantionParticles are touching
Particles are far apart
Macroscopic property: Fluid or not?
rigid fluid
Nanoscopic explanantion Particles are stuck Particles are NOT stuck together
Diagram of the nanoscopic.Add some wiggle and speed lines as appropriate
( ( (
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Explaining the Macroscopic by Describing the Nanoscopic
Solid Liquid Gas
Macroscopic property: Compressible or not? NOT compressible compressible
Nanoscopic explanantion Particles are touchingParticles are far
apart
Macroscopic property: Fluid or not?
rigid fluid
Nanoscopic explanantionParticles are
stuck Particles are NOT stuck together
Diagram of the nanoscopic.Add some wiggle and speed lines as appropriate (∆ to slide view)
( ( (((
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“Although the macroscopic world mostly looks continuous, underneath it is all particulate in nature - it’s just that the particles are very very very very very very very very very very very tiny.”• What macroscopic stuff is particulate or
quantized in nature - made of “units” that we can see?
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“Although the macroscopic world mostly looks continuous, underneath it is all particulate in nature - it’s just that the particles or quanta are very very very very very very very very very very very tiny.”• What macroscopic stuff is quantized or particulate
in nature - made of “units” that we can see.pencilshumansmarblessand ricepeas riceeggsbagel & donuts
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Select the statement(s) below that gives the best nanoscopic explanation as to why liquids and solids are incompressible.
1. the particles are very small.
2. the particles are stuck together.
3. the particles are touching each other.
4. the particles are aligned in a regular and repeating pattern.
5. the particles are polar so they are “sticky”
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Select the statement(s) below that gives the best nanoscopic explanation as to why liquids and solids are incompressible.
1. the particles are very small.
2. the particles are stuck together.
3. the particles are touching each other.
4. the particles are aligned in a regular and repeating pattern.
5. the particles are polar so they are “sticky”
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Select the statement(s) below that gives the best nanoscopic explanation as to why liquids or gases are fluid.
1. most of the particles are very small.
2. most of the particles are NOT stuck together.
3. most of the particles are touching each other.
4. most of the particles are NOT aligned in a regular and repeating pattern.
5. the particles are polar, so they are “sticky”
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Select the statement(s) below that gives the best nanoscopic explanation as to why liquids or gases are fluid.
1. most of the particles are very small.2. most of the particles are NOT stuck
together.3. most of the particles are touching each
other.4. most of the particles are NOT aligned in a
regular and repeating pattern.Again, while this is a true statement, but is not the
reason that the liquid and gas are fluid.
5. the particles are polar, so they are “sticky”
ParticlesPure or Mixture? Elements or Compounds?Atoms or Molecules?
Chapter 3
slide view
We are an allotrope of the element oxygen, O3.
☺☺
☺☺We are oxygen atoms
We are another allotrope of oxygen, O2
☺☺
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In the following slides, the boxes represent containers with “stuff” in them.Atoms are represented by circles.Different colored circles will represent different elements.
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
1. Which box(es) contain a pure substance ?
2. Enter 0 for none of the above
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ANSWER: The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 71. Which box(es) contain a pure substance?
2. Enter 0 for none of the above
AllotropesDifferent forms of the same element, caused by a different arrangement of the atoms of that element.
We are an allotrope of the element oxygen, O3.
☺☺
☺☺We are oxygen atoms
We are another allotrope of oxygen, O2
☺☺
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Allotrope - Different form of the same element Diamonds and Graphite
Oxygen gas, O2 and Ozone, O3
Allotropes of carbon
Buckminsterfullereneaka Buckyballs
Graphite
Diamonds
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain a mixture?
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ANSWER: The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain a mixture?
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain(s) a compound?
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ANSWER: The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain(s) a compound?
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
In which box(es) are the particles only molecules?
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ANSWER: The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
In which box(es) are the particles only molecules?
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain only a single element?
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ANSWER: The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain only a single element?
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
Which box(es) contain(s) a mixture whose particles are atoms and molecules?
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ANSWER: The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7
1. Which box(es) contain(s) a mixture whose particles are atoms and molecules.
2. Enter 0 for none of the above
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How are you feeling about the use of the terms:pure substance - mixturemolecules - atomselements - compounds
1. I think I can use all of these terms correctly most of the time.
2. I think I can use these terms correctly with a little more practice tonight.
3. I am feeling unsure about them, but I will work on them tonight, then ask for help tomorrow if I am still not clear.
4. I am feeling fuzzy about them, but have no intentions of trying to figure it out.
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7 a)b)c)
Label each box with only one label of the a) words
and one OR two labels of the b) words
and one OR two labels of the c) words
a) pure substance or mixture
b) element and/or compound
c) atoms and/or molecules
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The boxes below represent containers with “stuff” in them.
1 2 3 4 5 6 7 a) mx mx mx mx p p mxb) e e e e & c e c e & cc) a m m a & m a m m
Label each box with three labels:
a) pure substance or mixture
b) element and/or compound
c) atoms and/or molecules
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Classification of Matter
the most fundamentalform of matter
element
in a fixed ratio
chemically combined
2 or more elements
compound
Pure Substance
heterogeneous homogeneousaka: solution
in a variable ratio
physically mixed
2 or more substances
Mixture
All Matter
different
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Classifying MixturesHomogeneous (solutions) or Heterogeneous?
1 2 3 4 5
1. Which box(es) contain a heterogeneous mixture?
2. Enter 0 for none of the above
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Classifying MixturesHomogeneous (solutions) or Heterogeneous?
1 2 3 4 5
1. Which box(es) contain a heterogeneous mixture?
2. Enter 0 for none of the above
~ Heterogeneous mixtures have different properties in different regions of the mixture
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Classifying MixturesHomogeneous (solutions) or Heterogeneous?
1. Which box(es) contain a solution?
2. Enter 0 for none of the above
1 2 3 4
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Classifying MixturesHomogeneous (solutions) or Heterogeneous?
1. Which box(es) contain a solution?
2. Enter 0 for none of the above~ Does not vary in composition. All regions have the same
properties
1 2 3 4 Brass Soda water Air Ocean water
solid/solid Gas/liquid gas/gas solid/liquid
Copper and Zinc CO2 in Water O2 and N2 salt in Water
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Definitions
1. Heterogeneous mixtures–a) With your eyes: you can see the different partsb) May not be mixed uniformly throughout
2. Homogeneous mixture: aka solutiona) With your eyes: looks the same all overb) Mixed uniformly throughout
1. For instance: Sugar in water has same sweetness throughout
c) Specific types of solutions:
✴ Solid in Solid✴ Liquid in Solid ??✴ Gas in Solid
✴ Solid in Gas✴ Liquid in Gas ✴ Gas in Gas
✴ Solid in Liquid✴ Liquid in Liquid✴ Gas in Liquid
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Solution: Solid in Liquid
1. Salt in water - separate into ions
2. Sugar in water - stays together as molecules
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Solution: Liquid in Liquid
1. Mixed drink: Rum and Cokea) Alcohol and soda
2. Shirley Templea) Grenadine and ginger ale
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Solution: Gas in Liquid
1. Seltzera) CO2 and water
2. “Air” for fisha) O2 in water
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Solution: Solid in Gas(perhaps this is actually a suspension)
1.Dusta)Dirt in air
2.Pollena)Pollen in air
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Solution: Liquid in Gas(perhaps this is also a suspension)
1.Foga)Water in air
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Solution: Gas in Gas
1. Air a) nitrogen and oxygen
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Solution: Solid in Solid
1. Alloysa) Brass
b) Stainless steel
2. Gemsa) Ruby: red chromium
compounds in aluminum oxide
b) Sapphire: blue titanium in aluminum oxide
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Solution: Liquid in Solid
1. ????
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Solution: Gas in Solid
1. Marshmallows a) air in sugar puff
2. Canned whip creama) N2O in cream
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Separating mixtures
•Distillation
•Filtration
•Crystallization
•Sublimation
•Chromatography
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Distillation • Heat liquid to boil
• Produces steam
• collect and cool steam
• condenses steam back to liquid
• solid and liquid are separated
Distillation Video
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Filtration
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Crystallization
1. Crystallization results in the formation of PURE solid particles of one substance in order to SEPARATE the substance from the solution
2. When the solution is as concentrated as possible with a substance, adding more of the substance or allowing water to evaporate causes crystallization
3. ROCK CANDY- water and sugar solution, as water evaporates, solid candy crystals form
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Sublimation1. SUBLIMATION – The process
where a solid changes to a gas without melting
2. Can be used to separate two solids in a mixture when ONE solid sublimes but not the other…
Sublimation -- DRY ICE
Purple Haze: Sublimation of iodine
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Chromatography
1. Separates components of a mixture based on their ability to travel along another material
2. Usually the mixture (MOBILE PHASE) is a liquid or gas
3. The material (STATIONARY PHASE) is a solid
4. Different components in the solid will travel different distances
Paper chromatography
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The 4th State of Matter
The fourth state of matter is plasma. Plasma is an ionized gas, a gas into which sufficient energy is provided to free electrons from atoms or molecules and to allow both species, ions and electrons, to coexist. In effect a plasma is a cloud of protons, neutrons and electrons where all the electrons have come loose from their respective molecules and atoms, giving the plasma the ability to act as a whole rather than as a bunch of atoms. Plasmas are the most common state of matter in the universe comprising more than 99% of our visible universe and most of that not visible. Plasma occurs naturally and makes up the stuff of our sun, the core of stars and occurs in quasars, x-ray beam emitting pulsars, and supernovas. On earth, plasma is naturally occurring in flames, lightning and the auroras. Most space plasmas have a very low density, for example the Solar Wind which averages only 10 particles per cubic-cm. Inter-particle collisions are unlikely - hence these plasmas are termed collisionless.