THINK
What is matter?
Matter
Think – Pair - Share
SHARE
What do you think?
What do you think?
PAIR
Individually, think of what you know about “matter”. This was part of your 6 th grade science class. Write down what comes to mind when you think of
“matter”. 5 - 7 minutes
Now pair up with a partner (or team) and share your thoughts and ideas. One person serve are the recorder and put these on the construction paper.
5 – 7 minutes
Each team will then share their information with the class. Tape the construction paper up for other students to see.
Matter: Properties and Change http://www.youtube.com/watch?v=FSyAehMdpyI “The Nucleus: Crash Course Introduction To Chemistry” #1” 10:12
Matter, is a substance that has mass and also volume . The volume is determined by the space it occupies, while the mass is defined as a measure of how much matter is in an object. http://micro.magnet.fsu.edu/primer/java/scienceopticsu/powersof10/ size comparisons from milky way galaxy to quarks
What is matter? Explain your reasoning.
http://commons.wikimedia.org
Sunlight Water Electricity
Heat Smoke Earth’s Atmosphere
Early alchemists thought that everything was made of either earth, air, water or fire.
“The Elements” VHS
http://youtu.be/zUDDiWtFtEM “The New Periodic Table Song 3:00 min.
http://www.ncpublicschools.org/docs/accountability/testing/releasedforms/2009grade8periodic.pdf
DPI periodic table
The first letter is always capitalized.
In symbols with two or more letters, only the first letter is capitalized.
Chemistry Spoons Game
73
An atom will have the same number of electrons as protons.
Coach Lesson #1
Lithium atom (atomic #3 = protons) - An atom containing an equal number of protons (+) and electrons (-) is electrically neutral, otherwise it is positively or negatively charged and is known as an ion .
Atomic Mass = 7 (protons and neutrons)
Protons = positively charged
Neutrons = neutral (no) charge
Electrons = negatively charged
What particles are in the nucleus?
An atom is classified according to the number of protons (atomic #):
- the number of protons (atomic #) determines the chemical element ,
- and the number of neutrons determines the isotope of the element. ( i.e. carbon 12 and 14)
How do sizes of atomic particles differ?
(Quarks make up protons and neutrons.)
How is the size of atomic particles measured?
The nanometer is often used to express dimensions on an atomic scale:
- The diameter of a
atom, for example, is about 0.1 nm, and that of a
is about
20 nm.
Where are the protons and neutrons located?
2
(protons and neutrons)
Electron Orbitals/ Cloud/Energy Level/Shell Configurations
How many valence electrons are shown in this atom?
Valence electrons are those located in the outer most shell/level.
Valence Electrons
The valence is the number of outer shell/orbital electrons. These are the electrons available to take part in chemical reactions.
The periodic trend for valence works well for the representative elements, which are in groups 1, 2, 13, 14, 15, 16, 17, and 18
(the ‘tall’ parts of the table). Reading left to right, the valence for each of the main groups increases from one to 8. The noble gas elements, with 8 valence electrons, are especially stable.
Helium only has 2 valence electrons. Why is it in group 18?
Why are the noble gasses the “happiest” elements?
N
- Protons = 3 (atomic number)
N
- Neutrons = 4
Lithium (Li): One neutron is not shown.
- Mass Number/Weight = 7
(protons and neutrons)
1. What period is lithium in?
2. What group/family is lithium in?
3. How many valence (outer) electrons does lithium have?
- Electrons = 3
* The number of protons (+) and electrons (-) will be the same.
Elements above 92 are synthetic meaning they are
“manmade” and not found in nature.
1. How many protons (+) are shown?
2. What is the atomic mass?
3. How many neutrons
(neutral) are shown?
4. How many electrons (-) are shown?
5. How many valence (outer level) electrons are shown?
Classifications of elements
Some sources have astatine as a metalloid while others do not.
Atom Diagram Practice
“Build That Atom” Activity http://phet.colorado.edu/en/simulation/build-an-atom build an atom activity
A. What is the atomic number of boron?
B. What is the mass number of boron?
C. What family is boron in?
D. What group is boron in?
1. How many protons (+) are shown?
2. How many neutrons
(neutral) are shown?
3. How many electrons (-) are shown?
4. How many valence (outer level) electrons are shown?
“The Elements” VHS 50:52
Valence electrons can be determined by looking at the group/family.
Group 1 = 1 valence (outer) electron
Group 2 = 2 valence (outer) electrons
Periodic Table Color Coding Activity
Group 13 = 3 valence (outer) electrons, etc. (transition elements 3-12 will vary)
A group/family on the periodic table means the elements have similar chemical properties.
Elements of the same period have the same number of electron orbitals/shells.
Valence electrons are what determine the bonding ability of an atom.
Essential mineral elements : ( elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen present in common organic molecules) nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, chlorine, iron, manganese, zinc, copper, molybdenum, and nickel.
Beneficial elements: elements which promote plant growth in many plant species but are not absolutely necessary for completion of the plant life cycle : Silicon, sodium, cobalt, and selenium
Essential nonmineral elements; (elements taken up as gas or water): hydrogen, oxygen, and carbon
Some sources show astatine as a metalloid while other do not.
along zigzag line
Classifications of Elements
Why is hydrogen not connected to group 1?
Classifications of elements
34
Se
Seleniu m
77
84
Po
Polonium
209
Some periodic tables include astatine as a metalloid. Based on the site http://www.chemicalelements.com/groups/metalloids.html
astatine is not a metalloid. http://www.chemtopics.com/elements.htm
interactive periodic table
Metalloids are a chemical element with properties that are in-between or a mixture of those of metals and nonmetals. The seven elements commonly recognized as metalloids are boron, silicon, germanium, arsenic, antimony, astatine and tellurium. They or their compounds find uses in glasses, alloys or semiconductors. These are located along the zigzag line.
Metals
Notice that the metalloids and nonmetals are not included. Compare this section of the periodic table to the complete periodic table of elements.
Metalloids & Nonmetals
Metalloids
Some sources show astatine as a metalloid while other do not.
Nonmetals
Physical Properties: can be observed and measured without changing the kind of matter being studied; can be used to identify substances
Melting Point:
- The temperature at which a solid can change to a liquid.
- The temperature at which a pure substance melts is unchanging under constant conditions.
Boiling Point:
- The temperature at which a liquid boils.
- A substance changes from a liquid to a gas.
- Boiling temperature is unchanging under constant conditions for a given substance.
Density: Example: Man from Zambia
Assessment Probe: “Floating Logs”
Demo: Density Blocks
- a property that describes the relationship between the mass of a material and its volume
- Substances that have higher densities contain more matter in a given volume.
- The density of a substance will stay constant/the same.
Color: may be used to identify substances but not always
Physical Properties of Metals and Nonmetals
STC: “Finding the Conductor” 1.1
Physical Properties of Noble Gasses (Group/Family #18)
How are properties used to identify substances?
H
How are properties used to determine how elements and substances are used?
1. Why is aluminum used in airplanes?
2. Why is helium used in balloons instead of oxygen or hydrogen?
Chemical Property: any of a material's properties that becomes evident during a chemical reaction; that is, any quality that can be established only by changing a substance's chemical identity
1.
Can be used to help identify a substance Example: Man from Zambia
2.
Usually involves the substance’s ability to react or not react with another specific substance
Examples
Reacting with Oxygen (oxidation): The ability of a substance to burn is a chemical property that involves a substance reacting quickly with oxygen to produce light and heat. (i.e. iron rusts or apples turn brown).
http://www.youtube.com/watch?v=mjkuSm__G7s phosphorus reacting with oxygen
Reacting with Acids: The ability of a substance to react with an acid is a chemical property. Some metals react with various acids to form compounds. All metals do not react with all acids. Bases react with acids to form water and neutralize the acid.
Reactivity: the tendency of a substance to undergo chemical reaction, either by itself or with other materials.; reactivity is a chemical property of an element http://www.youtube.com/watch?v=Jy1DC6Euqj4 potassium reaction in water 20 sec.
http://www.youtube.com/watch?v=MTcgo46nxNE sodium reaction in water 48 sec.
These soft, silvery sodium chunks were cut with a knife and stored under oil. In air they turn white in seconds; exposed to water they generate hydrogen gas and explode in flaming balls of molten sodium.
http://www.youtube.com/watch?v=1bJBueGSC9M calcium reactivity with oxygen 27 sec.
(silver oxide (Ag
2
O) demonstration)
Less
Reactive
Helium
Physical & Chemical Properties
Substance Physical Property Chemical Property
Less dense than air Nonflammable
Wood
Baking Soda
Powdered Sugar
Rubbing Alcohol
Grainy texture
White powder
White powder
Clear liquid
Flammable/combustible
Reacts with vinegar to form bubbles (CO
2
)
Does not react with vinegar
Flammable/Combustible
Red Food Coloring
(demonstration)
Iron
Tin
Red color
Malleable
Malleable
Reacts with bleach and loses color
Reacts with oxygen (oxidation) to form iron oxide (rust) Ag
2
O
Reacts with oxygen to form tin dioxide
Physical or Chemical Property… What do you think?
Points to Consider
If the property changes, is a new substance formed? If not, it is a physical property.
If you still have the same substance after changing the property, it is a physical property.
http://www.glencoe.com/sites/common_assets/science/vir tual_labs/E21/E21.html
Is the change a physical or chemical change?
http://www.youtube.com/watch?v=vW9of4JYHY0 Chemical and Physical Changes 1:26
Physical Changes
Physical Change:
- The physical properties change but the type of substance stays the same.
- Matter changes is size, shape or form.
- There is no change in the chemical makeup of the substance(s) that are changed.
-
- Physical changes can be reversed.
Examples : cutting, changes in states of matter (melting, boiling, freezing), etc.
http://glencoe.mcgraw-hill.com/sites/dl/free/0078617650/160350/00044680.html
Brain Pop Chemical and Physical Changes program w/quiz (note: Cooking an egg is a chemical change.)
Phase Change
(mixing two or more substances)
(dissolving a substance)
Chemical vs Physical Changes (laptop review)
Chemical Change:
- properties change and a different substance is produced.
-
- Chemical changes cannot be reversed.
Examples : iron reacts with oxygen and water to form iron oxide (rust); silver reacts with oxygen to form silver oxide (tarnish)
Evidence of a chemical change
:
1.
Change in energy: temperature increase = exothermic chemical reaction temperature decrease = endothermic chemical reaction
2.
Color change: This is not when a color has been covered, for example dying, painting, etc.
3.
Formation of a gas: if in a solution, bubbles will often times been seen when the gas is formed
4.
Formation of a precipitate: when two or more solutions are combined and a solid is formed
STC: “The Burning Candle” 1.3 “Mixing the Solutions” 1.8 “Adding the Acid” 1.5
What evidence is there of a chemical change in these two pictures of the Statue of Liberty?
Sublimation: when a substance changes directly from a gas to a solid
Examples:
The forming of frost from water vapor
When dry ice forms: Dry ice is frozen carbon dioxide.
As it breaks down, it turns directly into carbon dioxide gas rather than a liquid http://www.youtube.com/watch?v=8tHOVVgGkpk dry ice bubbles 2:20; also shows properties of polar molecules water and detergent (surface tension)
Solid air fresheners
Apples brown (react with oxygen)
Physical change rearranges molecules but doesn't affect their internal structures. Some examples of physical change are:
- whipping egg whites (air is forced into the fluid, but no new substance is produced)
- magnetizing a compass needle (there is realignment of groups ("domains") of iron atoms, but no real change within the iron atoms themselves).
- boiling water (water molecules are forced away from each other when the liquid changes to vapor, but the molecules are still H
2
O.)
- dissolving sugar in water (sugar molecules are dispersed within the water, but the individual sugar molecules are unchanged.)
- dicing potatoes (cutting usually separates molecules without changing them.)
Chemical change is any change that results in the formation of new chemical substances. At the molecular level, chemical change involves making or breaking of bonds between atoms. These changes are chemical:
- iron rusting (iron oxide forms)
- gasoline burning (water vapor and carbon dioxide form)
- eggs cooking (fluid protein molecules uncoil and crosslink to form a network)
- bread rising (yeast converts carbohydrates into carbon dioxide gas)
- milk souring (sour-tasting lactic acid is produced)
- suntanning (vitamin D and melanin is produced)
Mini-Poster Analysis
1. Is a phase change a physical or chemical change? Explain.
2. What is the relationship between phase change and temperature?
3. What effect does phase change have on the volume of the substance/molecules? Density? Mass? Explain.
http://www.youtube.com/watch?v=czmQ2_ymaOo formation of ice crystals 37 sec.
4
1
Is the change a physical or chemical change?
2 3
5 6
Is the change a physical or chemical change?
1. Chemical 2. Chemical 3. Physical
4. Physical
5. Chemical 6. Chemical
1
Is the change a chemical or physical change?
2 3
4 5 6
Is the change a chemical or physical change?
1. Physical 2. Physical 3. Chemical
4. Physical 5. Chemical 6. Chemical
Chemical Changes Require Chemical Reactions
Chemical Reaction: when substances chemically combine to form new substances.
STC: “Reacting A Tablet” 1.7
MRE Lab
Endothermic Reactions = temperature decrease; Exothermic Reactions = Temperature increase
A chemical change involves a physical change, and can include but is not limited to the following:
Chemical changes do not change the mass, because according to the Law of Conservation of Mass/Matter, during a chemical reaction the mass of the reactants of the formula will always equal the mass of the products.
Chemical Reactions = Chemical Changes = New Substance(s) Formed
Chemical reactions are shown in the form of chemical equations.
Word equation: Sodium + Chlorine yields sodium chloride
Chemical equation: 2Na + Cl
2 reactants
2NaCl products
Coefficient = # of molecules in the compound
Subscript = # of atoms of the element
1.
What is the mass of the reactants? (Use your periodic table.)
2.
What is the mass of the products? ( Use your periodic table.)
3.
Does this reaction meet the “Law of Conservation of Mass/Matter”?
Explain.
Law of Conservation of Mass/Matter
: “Nuts & Bolts of Law of Conservation of Mass” or Simulation
- In a chemical equation, matter cannot be created or destroyed
- The mass of the reactants will equal the mass of the products.
STC: “Mixing the Solutions” 1.8
“Balancing Chemical Equations” practice
Chemical Reactions = Chemical Changes = New Substance(s) Formed
Chemical reactions are shown in the form of chemical equations.
Word equation: Sodium + Chlorine yields sodium chloride
Chemical equation: 2Na + Cl
2 reactants
2NaCl products
1.
What is the mass of the reactants? 116
- 2 Na atoms = 23 x 2 = 46
- 2 Cl atoms = 35 x 2 = 70
2.
What is the mass of the products? 116
- 2 Na atoms = 23 x 2 = 46
- 2 Cl atoms = 35 x 2 = 70
3.
Does this reaction meet the “Law of Conservation of Mass/Matter”?
Explain. Yes, because the mass of the reactants equals the mass of the products
Law of Conservation of Mass/Matter:
In a chemical equation, matter cannot be created or destroyed
- The mass of the reactants will equal the mass of the products.
STC: “Mixing the Solutions” 1.8
“Balancing Chemical Equations” practice
Balanced Chemical Equations
The coefficient shows how many total molecules are present. Multiply this by the subscript.
No subscript indicates that 1 atom is present.
Hydrogen = 4
Oxygen = 2
Hydrogen = 4
Oxygen = 2
Does this equation meet the “Law of Conservation of Mass/Matter”? Explain .
http://www.sciencespot.net/Media/blncact.pdf
Balancing Act WS
Balance the following chemical equations.
Reactants Products
1. Na + Cl
2
NaCl
2. H
2
+ Cl
2
3. CO
2
+ H
2
4. 2NO + O
2
HCl
CO + H
2
O
2NO
2
5. 4Fe + 3O
2
2Fe
2
O
3
Note: You may only add coefficients when balancing equations, not subscripts.
One of the equations is balanced.
1.
2 Na + Cl
2
2. H
2
+ Cl
2
3. CO
2
+ H
2
4.
2 NO + O
2
5.
4 Fe + 3O
2
2 NaCl
2 HCl
CO + H
2
O
2 NO
2
2 Fe
2
O
3
Balanced chemical equations support the law of conservation of mass/matter. Explain why.
The chemical reaction for photosynthesis
Reactants yield Products
Reactants
6 carbon
24 oxygen
24 hydrogen
Products
6 carbon
24 oxygen
24 hydrogen
Chemical Equation for Cellular Respiration
Reactants yield Products
Reactants
6 carbon
24 oxygen
24 hydrogen
Products
6 carbon
24 oxygen
24 hydrogen
Compounds and Mixtures
- Elements combine to form compounds.
- Compounds have a chemical formula.
- Elements that combine DO NOT keep their original properties.
- May be natural or synthetic (manmade)
Substances combine but NOT chemically; they keep their original properties
Have the same consistency throughout
Heterogeneous
Do not have the same consistency throughout
What is the difference between a compound and a molecule?
1.
A molecule is formed when two or more atoms join together chemically.
2.
A compound is a molecule that contains at least two different elements .
- All compounds are molecules but not all molecules are compounds.
Example:
- Molecular hydrogen (H
2
), molecular oxygen (O
2
) and molecular nitrogen
(N
2
) are not compounds because each is composed of a single element.
They are diatomic molecules because in nature they do not exist as individual atoms.
- Water (H
2
O), carbon dioxide (CO
2
) and methane (CH because each is made from more than one element.
4
) are compounds
- The smallest bit of each of these substances would be referred to as a molecule.
Cannot be changed into a simpler substance
Pure substances composed of two or more types of elements that are chemically combined
STC: “Our Ideas About Pure Substances and Mixtures”
- A compound is a type of matter that forms when two or more different elements combine chemically. Two or more atoms bonded together is a molecule of the substance that is formed.
- When atoms combine chemically, they do not retain their original properties. How do the following compounds provide evidence of this?
In the compounds below, compare the properties of elements before and after chemical bonding has occurred.
Examples: Chemical formulas for common substances
2
chemical formula for 1 water molecule
Subscript: #of atoms present of the element to the left no # as with oxygen means there is 1 atom present
C
12
H
22
O
11
NaCl
O
2
NaClO
HCl
NaCl sucrose table salt oxygen (diatomic element) household bleach hydrochloric acid sodium chloride (table salt)
NaHCO
3
HC
2
H
3
O
2
H
2
O
NH
3
CO
2
H
2
O
2
Activity: Identification of Element & Compounds in Products
“Analyzing Formulas” practice baking soda vinegar water ammonia carbon dioxide hydrogen peroxide
2
• Water is a compound formed from two atoms of hydrogen and one atom of oxygen; H
2
0
_ and + indicates the charged area of the molecule
• In their form as elements, hydrogen and oxygen are gasses. They both are also highly flammable.
+
_
+
• When combined in this 2 to 1 ratio, they form a liquid that is not flammable.
“Biological Molecules: “You Are What You Eat” complete study guide http://www.youtube.com/watch?v=H8WJ2KENlK0 (14:09)
Sodium Chloride (table salt) is a combination of 1 sodium atom and 1 chlorine atom;
NaCl.
• In their form as elements, sodium is a highly explosive solid that explodes in water and chlorine is a toxic gas. http://www.youtube.com/watch?v=9bAhCHedVB4&safe=active
• When combined in a 1 to 1 ration, they form table salt which is a white solid that dissolves in water.
6
12
6
What elements are in a molecule of sugar?
“A Compound Problem” Practice
What elements are in the compounds below and in what ratio? What are the properties of the elements?
What elements are common is both of these compounds?
How are they different?
Carbohydrate Compounds – the main source of energy for our bodies
What elements are in these molecules? What is a better source of carbohydrates, simple or complex carbohydrates?
What elements are in a molecule of protein?
In nature, matter is continually recycled.
What elements are in the essential nutrient protein?
What elements are in lipid molecules?
Common Name epsom salt moth balls baking soda table salt cane sugar sulfuric acid white vinegar nail polish remover ammonia boric acid marble,limestone,chalk road salt garden lime corn syrup
Chemical Name acetic acid acetone ammonium hydroxide boric acid calcium carbonate calcium chloride calcium hydroxide glucose magnesium sulfate naphthalene sodium bicarbonate sodium chloride sucrose sulfuric acid
Common Chemicals
Chemical Formula
CH
3
COOH + H
2
O
CH
3
COCH
3
CH
3
+ H
2
O
H
3
BO
3
CaCO
3
CaC l2
Ca(OH)
2
C
6
H
12
O
6
+ H
2
O
MgSO
4
+ 7H
2
O
C
10
H
8
NaHCO
3
NaCl
C
12
H
22
O
11
H
2
SO
4
1.
A molecule is what you get when any atoms join together.
2.
A compound is what you get when atoms of two or more different elements join together.
join together.
3.
All compounds are molecules, but not all molecules are compounds.
3.
All compounds are molecules, but not all molecules are compounds.
-
Water is a molecule because it is made from atoms that have been make water are not all the same - some are oxygen and some are hydrogen .
oxygen and some are hydrogen .
- Oxygen in the atmosphere is a molecule because it is made from two atoms of oxygen. It is not a compound because it is made from atoms of only one element - oxygen. This type of molecule is called a diatomic molecule, a molecule made from two atoms of the same type.
The Difference Between Compounds and Mixtures
Mixture - A physical blend of two or more substances that are
NOT chemically combined .
Compound - A substance that contains two or more elements
CHEMICALLY combined in a fixed proportion . The elements do not retain their original properties .
Compound is chemically combined, mixture is not chemically combined.
*Cake would be a compound because all of the ingredients are together to make batter you cannot see the individual components (eggs, flour, sugar, etc.)
*Trail mix would be a mixture because you can see every individual item (M&M, peanuts, raisins, pizza, etc.)
“Introduction to Matter”
Mini-poster examples
STC lab activities: “Comparing the Two Mixtures” 1.6 “Filtering a Mixture” 1.2
“Separating a Mixture” 1.4
Mixture
Ways to separate mixtures:
- Filtration
(separates large particles from small)
- Evaporation
(use boiling point)
- Centrifuge
(use density)
- Magnet
- Sifting
- tin + copper = pewter - copper + tin = bronze
(more) (less) (more) (less)
Steel is an alloy of iron, with carbon being the primary alloying element.
The air you breathe is made up of about 21% oxygen, 78% nitrogen, and small amounts of other gases like argon, carbon dioxide and methane.
Homogenous or Heterogeneous Mixtures… Do you know?
#1 M & M #2 Salad #3 Kool Aid drink #4 Fruit Loops
#5 Milk #6 Cake Batter #7 Chocolate Chip Cookie #8 Hot Chocolate
#9 Trail Mix #10 Tap Water #11 Smoke #12 Clear Seawater