Post on 03-Jan-2016
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Directions for Copying Notes
When recording notes from power point slides for this class, copy ONLY THOSE SLIDES THAT ARE NUMBERED.
Make sure that you number each slide in your own notes as well because having every slide in order is how you will receive full credit on your science notebook. Notes without numbers will not be accepted for grading.
Un-numbered slides are presented as examples for class discussion; they do NOT contain facts that you must study for the test.
PA Standards Addressed in Chapter 1: Introduction to Matter
3.2.7.A1 – Differentiate between elements, compounds and mixtures; explain how materials are characterized by having a specific density.
3.2.7.A2 – Identify atoms as the basic building blocks of matter; elements are composed of only one type of atom.
1. CHP. 1 - INTRODUCTION TO MATTER
Matter is anything that has mass and takes up space.
Everything in the universe is made up of matter.
2. PROPERTIES OF MATTER
Examples: hardness, texture, temperature, shape, flammability, size, & color
“States” of matter include solid, liquid & gas; state depends on temperature
3. Characteristic Property – a quality that NEVER changes & so can be used to identify a particular
type of matter While some properties can change (ex: size
or shape of a piece of wood), characteristic properties remain the same
EVERY sample of a particular kind of matter will have the same characteristic properties
An unknown sample of matter can then be identified by looking at its characteristic properties
Example of a Characteristic Property: The Flame Test of Unknowns http://www.youtube.com/watch?v=jJvS4uc4T
bU
Click the link above to view the way that different solid substances burn with their own vividly colored flames!
4. Common Characteristic Properties used in Testing Unknowns: Boiling Point – the temperature at which
a liquid boils is characteristic for each kind of substance. Ex: pure water always boils at 1000 C
Liquids that may look alike can be identified by testing their boiling points
Melting Point – the temperature at which a solid melts is characteristic for each kind of substance
Quiz: In what state will you find each substance at room temp. (200 C)?Substance Melting Point 0C Boiling Point 0C
Water 0 100
Chloroform -64 61
Ethanol -117 79
Propane -190 -42
Table Salt 801 1,465
5. Identification of an unknown substance requires comparing at least 2 characteristic properties for a match
This is necessary since different substances may share one characteristic property
6. Changes in Matter – two types:
Physical Changes alter the form or appearance of a substance, but do not change its identity.
Chemical Changes cause a substance to break apart (or combine with other substances) to form something new.
Quiz: Physical or Chemical Change?
The first video clip shows a glass of milk that this boy left in his room for 2 weeks
The second video clip shows a watermelon thrown off a roof
http://www.youtube.com/watch?v=q25WifJxXZ8
http://www.youtube.com/watch?v=3OgJjsOGx8I
7. Classifying Matter: Two Categories Based on Composition Mixture – when 2 or more kinds of matter
are placed together, but are NOT chemically combined into one substance; this means each kind of matter keeps its own properties; often they can easily be separated.
A) Solution – a mixture that is so well mixed that the individual kinds of matter can’t be distinguished
B) Suspension – a mixture in which different kinds of matter can be seen separately. Ex: oil & vinegar
Pure Substance – made of only ONE kind of matter with 1 set of properties; Ex: elements or compounds
Solutions Don’t Have to be Liquids
Often man has found it useful to melt down 2 or more pure metals and mix them together.
Once they have been thoroughly stirred and then allowed to harden, we call this solid solution of metals an alloy
Ex: copper + tin makes bronze
Ex: copper + zinc makes brass
Ex: copper + silver makes sterling silver
Examples: Mixtures and Pure Substances
8. Element – one kind of pure substance Elements cannot be broken down into simpler
substances There are over 100 elements known at
present Many familiar elements are metals while
some are nonmetals Elements are abbreviated with 1 or 2 letter
symbols (always starting with a capital letter)
Periodic Table of Elements
Common Elements – note that some symbols are abbreviations of the original Latin names
9. Compounds – matter consisting of 2 or more elements that are chemically combined to form one pure substance The properties of a compound are different
from the properties of the elements it contains Ex: Sodium is an explosive metal, and
chlorine is a poisonous gas, but when combined to make sodium chloride (table salt) they become harmless and edible
Compounds are abbreviated with element symbols and subscript numbers:
H2O (water) CO2 (carbon dioxide)
10. Ways of Measuring Matter
Weight – a measure of the force of gravity pulling you downward against a scale; this quantity will change depending on the pull of gravity
Mass – NOT the same as weight; it is a measure of the amount of matter contained in an object
11. Standardized Measurement
Weight and Mass are measured in units called grams
Volume is measured in units called either cubic centimeters (cm3) for solids or milliliters (ml) for liquids
1 cm3 is a volume equal to 1 ml
Examples of Mass
Canned goods at the grocery store now show BOTH the English measure for weight (ounces) and the metric mass (grams):
PAUSE HERE TO COVER METRIC MEASUREMENTS… Your teacher will provide a handout as #12
13. Density - another way to measure matter Density is a measure of how much mass of a
substance is contained in a certain volume Density has to be calculated by
comparing mass and volume: Density = Mass
Volume
(Think of “Department of Motor Vehicles” – DMV)
14. Comparing Densities
If a great deal of matter is packed into a small space, this gives a very high density value
If the matter is more loosely packed the density value is low
Water has a density of 1 g/ml (meaning there is 1 gram of water per each 1 milliliter)
15. Density is a characteristic property
Density is the same for all samples of a substance Ex: pure gold always has a density that measures
19.3 g/cm3
Since density remains the same, it can be used to identify types of matter Gold bars Tiny gold nuggets
Material covered on the first test STOPS HERE
16. The Smallest Possible Particles of Matter An atom is the smallest particle of an element
that keeps all the properties of that substance
Back in 440 B.C. Democritus gave us the name atom; it is taken from the Greek “atomos” meaning uncuttable
17. Scientific Ideas About Atoms In 1802 John Dalton carried out
experiments with elements and recorded his conclusions
Today we refer to his ideas as the Atomic Theory as listed here:
a) Atoms cannot be broken into smaller pieces
b) In any single element, all the atoms are exactly alike
c) Atoms of different elements are different
18. (Atomic Theory Continued)
d) Atoms of 2 or more elements can combine to form compounds
e) Atoms of each element have a unique mass
f) The masses of the elements in a compound are always in a constant ratio
19. Combining Atoms to make Compounds A molecule is a group of atoms that are joined
together to act as a single unit; this molecule is the smallest piece of a compound
A chemical bond is the force that holds the atoms of the molecule together
20. Atomic Models
Today we have scanning tunneling microscopes that can show us tiny images such as gold atoms
21. Separating Elements from the Earth for Our Use
Only a few elements can be found in a pure form in the Earth
In 1848 John Sutter found several gold nuggets in the river near his mill; this discovery sparked the California gold rush
Prospectors used the high density of gold to separate dust and nuggets from the stream bed by “panning”
22. Another Separation Technique
Most elements cannot be found in their pure state
Ore is any rock that contains useful metals combined with other substances
Ores are mined from the Earth and then a complex series of steps is used to isolate the useful metal
The last step in this process is called electrolysis which means “electric cutting”
Video: “Ore to More – the Story of Copper” Click on this link to see the process of
removing copper from rocklike ore. The final step will show the use of electric current in “electrolysis” to purify the copper.
http://www.youtube.com/watch?v=RmaGh4g1JtY&feature=related
Element – just one kind of
matter
Compound – grouping
of 2 or more elements
Molecule of an Element
(chemical bonding of the
same kind of atoms)
Atoms
(smallest
individual
pieces)
Molecule of a
Compound (chemical
bonding of different
kinds of atoms)
Pure Substances – cannot
be easily broken down
Video Credits
Flame Test demonstration: http://www.youtube.com/watch?v=jJvS4uc4TbU
Curdled Milk: http://www.youtube.com/watch?v=q25WifJxXZ8
Picture Credits – those graphics not listed below were taken from clip art Periodic Table of Elements: http://www.google.com/imgres?
imgurl=http://www.chemicalelements.com/graphics/table.gif&imgrefurl=http://www.chemicalelements.com/&h=305&w=563&sz=50&tbnid=DmH8Gf33p0-pwM:&tbnh=68&tbnw=125&prev=/search%3Fq%3DPeriodic%2Btable%26tbm%3Disch%26tbo%3Du&zoom=1&q=Periodic+table&usg=__Nb4xZeHI8TWANtFba9KUGUOVJgo=&sa=X&ei=OVUXTty1HOqEsALd2vlV&ved=0CFgQ9QEwBg
Table of Common Elements: http://chestofbooks.com/food/household/The-Profession-Of-Home-Making/Table-Of-Common-Elements.html
Canned Goods: http://pzrservices.typepad.com/.shared/image.html?/photos/uncategorized/2008/09/26/1970s_canned_food.jpg
Water molecule: http://en.wikipedia.org/wiki/Properties_of_water Image of Gold Atoms: http://www.physics.purdue.edu/nanophys/stm.html
Picture Credits (continued)
Scanning Tunneling Microscope: http://www.google.com/imgres?imgurl=http://www.jaist.ac.jp/ms/english/research_list/equipments/images/STM_fig-STM_new.jpg&imgrefurl=http://www.jaist.ac.jp/ms/english/research_list/equipments/STM.html&h=1195&w=1600&sz=1343&tbnid=7xIb-8pCAC8_hM:&tbnh=102&tbnw=136&prev=/search%3Fq%3Dscanning%2Btunneling%2Bmicroscope%2Bdiagram%26tbm%3Disch%26tbo%3Du&zoom=1&q=scanning+tunneling+microscope+diagram&usg=__uB9MSl9heFTERkB0cv-VKEynXjY=&sa=X&ei=eKobTqqULore0QHB4rW5Bw&ved=0CGUQ9QEwCQ
Pyrite: http://www.google.com/search?sourceid=navclient&ie=UTF-8&rlz=1T4GFRD_en___US219&q=photo+of+oil+and+vinegar+mix#sclient=psy&hl=en&rlz=1T4GFRD_en___US219&source=hp&q=photo+of+pyrite&aq=f&aqi=g-v1&aql=&oq=&pbx=1&bav=on.2,or.r_gc.r_pw.&fp=6052ac049b0c2d47&biw=1024&bih=533