Improvements
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Transcript of Improvements
ImprovementsMake sure the study guide flow chart coincides with the powerpoint, make students give the examples
maybe (don’t include on list)!
Hang a sugar cube in water and watch it dissolve. It’s a physical change, but it looks chemical! (p.234)
Big difference btwn mixtures n compounds – retain physical properties & separate by physical means
Shine laser through solutions, colloids, and suspensions
Get better at making smoke colloid for lazer
More stress on size of particles for mixture, check on what’s a colloid and about
Elephant toothpaste, other catalyst demo?, cut light sticks open, denture cleaner for rate of reaction
Smash jolly rancher or other brittle object (peanut brittle), stretch taffy, gummie bear experiment
Definition of brittle?
Reuse the copper nitrate made in the silver nitrate reaction to make precipitate with (NaOH I think?)
Make everything flow! Create a mixture out of stuff, then separate it!
You can mix your own nail polish! Look it up!!!!
OIL BASED PAINT – SUSPENSION, LAYTEX COLLOID
Create notes outline or something…reading guide that goes with this with blanks for more info
Heterogeneous Mixtures
• Colloids
• Solutions – do blue bottle clock reaction!!!
• Boil coke to separate the water out!
• Mentos and coke experiment!
Classification & Properties of Matter
Bell Work 11/22/11 – 1 minute
New bell work titled “CLASSIFICATION OF MATTER”
1. What are 5 ways you could classify shoes?
2. Copy the classification of matter chart into your notes.
Schedule• Friday– Matter Chart
• Colloids• Separating mixtures• Index cards?• HW 1- 11 on C &PPP/CQ• Return tests?
• Monday– Chemical & Physical Changes– Bonus opp!!– HW
• Tuesday– Quiz?– Chemical & Physical Properties– HW bonus!
Study
Today you are going to…take notes on the classification of matter
So you can…identify each matter type & begin thinking of matter on a chemical level
You’ll know you’ve got it when you can • Complete the Matter flow chart and put different
substances into the correct category based on their properties
Classification of Matter• Matter is classified based on its composition.
• Composition means ______________________
• For next slides, need:– Jello, laser, pop, smoke, Jello, laser, pop, smoke, – Alcohol & waterAlcohol & water– Jar of salt or sugar, jar with element in it, Jar of salt or sugar, jar with element in it,
solution, colloid, suspensionsolution, colloid, suspension– Make solution of salt, alcohol, and water!Make solution of salt, alcohol, and water!• Then separate it! (add sand too)Then separate it! (add sand too)
Bell Work DAY 1 – 1 minute
New bell work titled “CLASSIFICATION OF MATTER”
1. Matter is classified based on _____?
MATTERMixtures
Homogeneous Mixture
Heterogeneous Mixture
Pure Substances
Elements Compounds 1 kind of atom 2+ elements
chemically combined
On periodic table
Solutions
same throughoutNOT same
throughout
salt, CO2, H2O, sugar, rust,
NaCl NaCl
(iron oxide) (iron oxide) solute – is
dissolved solvent – does
dissolving
Colloids Suspensions
salt water salt water pop
Kool-Aid
Only 118 known elements!
Ex. gold, iron, oxygen, helium
Sodium, chlorine Sodium, chlorine
0.01 – 1 nm particles
1 - 1000 nm particles
particles over 1000 nm
Scatter light “Tyndall effect”
latex paint Jell-O
mayonnaise
can filter, settle out
orange juice muddy water
What kind of matter?
How are colloids & suspensions different?
• Suspensions settle out faster and can be filtered.
• DO HW!
Bell Work DAY 2 – 1 minute
New bell work titled “CLASSIFICATION OF MATTER”
1. Practice matter chart with note cards.
Bell Work 12/5/13 – 7 minutes
Do 2nd Page of study guide (page before homework)
Today you are going to…take notes on separating mixtures & the types of colloids
So you can…separate mixtures!
You’ll know you’ve got it when you can • Separate mixtures.
Separating Mixtures• Magnet!
– Look at ze magnet!Look at ze magnet!
• Filtering – pouring liquid through a porous paper to separate particles based on size– Filter muddy waterFilter muddy water
• Decanting – pouring less dense mixture off the top of a liquid mixture– Decant density rainbowsDecant density rainbows
• Dissolving– Chromatography Do it!Do it!
• Filter paper, muddy water, alcohol & water, mixture with Filter paper, muddy water, alcohol & water, mixture with magnet in it, salt & alcohol, hotplate magnet in it, salt & alcohol, hotplate
• Distilling – boiling & condensing
Types of colloids1. Gel (aka Sol) - solid particles in a liquid.
Jell-O, jelly
2. Emulsion - two immiscible liquidsMilk, mayonnaise
3. Foam - gas particles trapped in liquid or solid. Whipped cream, root beer foam, ivory soap
4. Aerosol –small particles of liquid or solids in gas
Clouds, smoke
Jello, sodium thiosulfate & projector, soap oil Jello, sodium thiosulfate & projector, soap oil
Emulsions – liquid in liquid colloid• Immiscible – substances will not mix together;
ex: oil & water• Emulsifier – enables immiscible substances to
mix; ex: soap• Emulsion – mixture of 2+ mixtures that are
normally immiscible– Butter, mayonnaise, milk– 2 bottles – one with oil & water, one with oil, 2 bottles – one with oil & water, one with oil,
soap, and water, pass around have students soap, and water, pass around have students shake, see what it’s like everyday aftershake, see what it’s like everyday after
Bell Work – 5 minutes
1. Two liquids that won’t mix are called ___.
2. A substance that makes them mix is a ___.
3. The resulting mixture is called a ____. Which type of mixture is it?
4. It will scatter light, which is called the _____.
5. Identify the parts of the equation below.
2 K + 2 H2O 2 KOH + H2
Bell Work DAY 3 – 1 minute
New bell work titled “CLASSIFICATION OF MATTER”
1. Practice making chart!
Today you are going to…take notes on chemical & physical changes and chemical and physical properties. (You’ll also witness some chemical and physical changes.)
So you can…tell when chemical reactions occur and how they affect matter.
You’ll know you’ve got it when you can • Classify changes as physical or chemical and list
possible identifiers for each.
Materials List for Physical & Chemical ChangesClock water (150 mL KOH solution (1 molar), 150 mL dextrose (glucose) solution
0.4 molar, mix equal parts in two bottles just before class, 3-4 drops methene blue solution to one, enough indigo carmen solution to other (enough to get it yellow)
http://www.youtube.com/watch?v=mxuJ8IOHAlk
Color changing pencil
Bang snaps (high at wall in dark)
NaOH and CuSO4 or FeCl3 or NiCl
Silver nitrate solution & penny
Rust bottle
Light stick (2 test tubes)
Food! (kid eat it)Ammonium nitrate (or 32g barium hydroxide octahydrate &17g ammonium thiocyanate (or could use ammonium nitrate or
ammonium chloride))
18 molar hydrochloric acid
Sugar cubes & dental floss, cups, water
Mentos & pop? Baking soda & vinegar?
Chemical & Physical ChangesPass 3 Magic Water Bottles Around and magic pencil around!Pass 3 Magic Water Bottles Around and magic pencil around!
Chemical Change • A change in which a new substance is
formed
• Possible signs of a chemical change– smoke, gas produced, fire, smell change,
sound, light, change in color, temperature change, precipitate forms
• Precipitate – a solid formed in a reaction Precipitate – a solid formed in a reaction between two liquids (do on next slide)between two liquids (do on next slide)
– These are only possible signs. Just These are only possible signs. Just because you see them doesn’t mean a because you see them doesn’t mean a chemical change definitely occurred.chemical change definitely occurred.
Chemical Change • Guaranteed sign of a chemical change
– new substance is formed
NaOH + CuSO4 CuOH2 + NaSO4 blue NaOH + FeCl3 FeOH3 +NaCl orange NaOH + NiCl NiOH2 + NaCl light green
The parts of a chemical equation• Reactants
• Products
• Yields
2 Na + 2 H2O 2 NaOH + H2
copper + silver nitrate yields silver and copper nitrate
Cu + 2 AgNO3 2 Ag + Cu(NO3)2
• Conservation of matter – matter cannot be created nor destroyed
Examples of Chemical Changes • Iron combines with oxygen to form iron oxide (rust)
4Fe + 3O2 --> 2 Fe2O3
Look at rusty water!!Look at rusty water!!
• A light stick – you break it open, the chemicals mix to form a compound which glowsglows.
cyalume + H2O2 → trichlorophenol + CO2
Examples of Chemical Changes • A firecracker – loud sound, smell, & light
produced as it explodes…no longer a fire cracker! (Firecracker)Firecracker)
• Digestion of food (student demo)C6H12O6 (aq) + 6 O2 (g) → 6 CO2 (g) + 6 H2O (l) + heat
Examples of Chemical Changes • A rotten egg – It has decomposed. When it
rots, there’s a new smell & it’s no edible.– Hydrogen sulfide (H2S) has formed! Birds need
sulfur for their feathers.– Rotten eggs float!!
Endothermic & Exothermic Reactions
• Ammonium Nitrate and water- produces an endothermic reaction– the temperature decreases because heat is being
absorbed & change into chemical energy
NH4NO3 (s) H2O→ NH4+ (aq) + NO3 (aq)
• 18 molar sulfuric acid and water- produces an exothermic reaction (thermite link)
– the temperature increases because heat is being released.
H2SO4 + H2O → H3O+ + HSO4− H2SO4 + Heat
Endothermic Reaction
• 32g barium hydroxide octahydrate
• 17g ammonium thiocyanate (or could use ammonium nitrate or ammonium chloride)
Ba(OH)2.8H2O (s) + 2 NH4SCN (s)
Ba(SCN)2 (s) + 10 H2O (l) + 2 NH3 (g)
Speed of Chemical Reactions
Chemical reactions can happen slowly or quickly!
Speeding Up Chemical Reactions
MAKE THE PARTICLES INTERACT MORE QUICKLY!
1. Increase Surface Area (Crush the reactants or dissolve them in water)Antacids in film canister or graduated cylinders!Antacids in film canister or graduated cylinders!
2. Heat the reactants (heat & cool light sticks!)(heat & cool light sticks!)
3. Stir the reactants
4. Add a catalyst a substance that speeds up/slows down chem. reaction
CATALYST DOES NOT REACT
Physical Change
• A change in which the matter is altered but remains the same substance.
• Changes size, shape, or state (phase) of matter.
• STILL THE SAME SUBSTANCE(S)
Examples of a Physical Change
• Tearing a sheet of paper
• Making a milkshake
• Melting iron
• Melting an ice cube
• Boiling water
• Grinding & brewing coffee
• Making Kool-Aid
• Dissolving salt
Materials List for Physical & Chemical PropertiesAlcohol to burn
Wire
Mallet
Penny
Jolly rancher
Taffy
Syrup
Oil
Water
Chemical & Physical Properties
Properties of Matter
• Property - a characteristic that describes something; what it looks like, what it’s capable of doing
• A property can describe how an object looks, feels, or acts.
• Two main kinds of properties– physical properties – chemical properties
Bell Work 12/4/13 – 4 minutes
1. Do # 21-24 on the “Chemical and Physical Properties/changes Questions 2013” worksheet.
Today you are going to…take notes on chemical & physical changes and chemical and physical properties. (You’ll also witness some chemical and physical changes.)
So you can…identify a property as chemical, physical intensive, or physical extensive.
You’ll know you’ve got it when you can • Answer the questions on the worksheet
Chemical Property • A characteristic of a substance that
indicates that it can undergo a chemical change. – describes how the matter interacts with other
forms of matter– A chemical reaction must be observed to
observe a chemical property
– Gasoline – combustible
Examples of Chemical Properties• Flammable - flash point < 100oC
• Combustible - flash point of 100oC or higher
• Corrosive - will “eat away” a metal
• Caustic – will “eat away” your skin
• Explosive – capable of making an explosion on its own energy
Medication Warnings
• These warnings are These warnings are put on the medicine to put on the medicine to prevent or slow down prevent or slow down chemical reactions.chemical reactions.
Physical Property
• Characteristic of a substance that does not involve a chemical change
• Two main types of physical properties– Intensive– Extensive
Intensive physical properties • DOES NOT depend on the quantity of
matter (how much there is); depends on the type of matter
– Color– Density– State (phase)– Temperature– Freezing Point, Melting Point, Boiling Point
Intensive physical properties • DOES NOT depend on the quantity of
matter (how much there is); depends on the type of matter
– Conductivity – conducts electricity or energy– Malleable- able to be pounded into sheets– Ductile- able to be stretched into a wire– Brittle- breaks easily (like peanut brittle!)– Viscosity – resistance to flow (similar to thickness)
WireWire
Penny & mallet!Penny & mallet!
Jolly rancher & taffy!Jolly rancher & taffy!
Syrup, oil, & water!Syrup, oil, & water!
Intensive physical properties • Does not depend on the quantity of matter
(how much there is); depends on the type of matter– Five gallons of water will have the same
density, freeze at the same temperature, and is in the same state as 2 gallons of water.
– A stack of 1,000 papers will the same color, state, and as a stack of 5 papers.
– 1 lb or 1 ounce of copper (Cu) can both be drawn into wire (Both are _____________.)
Extensive physical properties
• Depends on quantity of matter (how much there is)
• Volume, size, mass, length, height, weight
• These change with the quantity of matter– Five gallons of water will have more mass then
2 gallons of water.– A stack of 1,000 papers will be much higher
than a stack of 5 papers.– 1 lb of Cu has more volume than 1 ounce of Cu
Intensive or Extensive?1. Powdered sugar is a white powder.
2. Water is a clear liquid.
3. The powdered sugar weighs 2 lbs.
4. Silver is malleable.
5. Density of 5.5 g/mL
6. A piece of copper weighs 7 lbs.
7. Helium is less dense than air
8. The paperclip has a mass of 1 gram.
9. The paperclip has a shiny luster.
10. A cup of water has a volume of 4 liters.
STOP
Chemical or Physical?If physical, Intensive, or Extensive?
1. The paperclip has a shiny luster.
2. The paperclip reacts with oxygen to form rust.
3. The paperclip has a density of 3.2 g/cm3
4. Sugar dissolves in water.
5. A aluminum is ductile.
6. Hydrogen gas reacts with oxygen gas to form water.
7. You can cut sodium with a knife.
8. Sodium reacts violently with water.
Faraday Lecture!
• Reactant– Starting materials (Left side of equation)– React together
• Product– Ending materials (right side of equation)– Produced by reaction
The parts of a chemical equation• Coefficients
• Subscripts
• Yields
• Products
• Reactants
2 H2O 2 H2 + O2
copper + silver nitrate yields silver and copper nitrate
Cu + 2 AgNO3 2 Ag + Cu(NO3)2
• Conservation of matter – matter cannot be created nor destroyed
Products! Reactants!
• FOR CHEMICAL AND PHYSICAL PROPERTIES HAVE STUDENTS READ A PARAGRAPH DESCRIBING A SUBSTANCE AND HAVE THEM PICK OUT WHICH IS WHICH
Chemical or Physical?If physical, Intensive, or Extensive?
1. The paperclip has a shiny luster.
2. The paperclip reacts with oxygen to form rust.
3. The paperclip has a density of 3.2 g/cm3
4. Sugar dissolves in water.
5. A aluminum is ductile.
6. Hydrogen gas reacts with oxygen gas to form water.
7. You can cut sodium with a knife.
8. Sodium reacts violently with water.
Bell Work 11/14/11 – 3 minutes
1. In the above reaction, sodium and water are the ______________ and sodium hydroxide and hydrogen gas are the ______________.
2. W5SAYW
Comparing Physical and Chemical Properties
Substance Physical Property Chemical Property
Helium Less dense than air Nonflammable
Wood Grainy texture Flammable
Baking soda White powder Reacts with vinegar to produce bubbles
Powdered sugar White powder Does not react with vinegar
Rubbing alcohol Clear liquid Flammable
Red food coloring
Red color Reacts with bleach and loses color
Iron Malleable Reacts with oxygen
You can observe physical properties without changing the identity of the substance. You can observe chemical properties only in situations in which the identity of the substance could change.
Bell Ringer 11/3/11
1. What chemical and physical changes were observed at the beginning of class?
1. Evidence?
2. How many of each type of atom are in the equation below?
3. Identify the reactant(s) and the product(s).
H2(g) + O2 (g) H2O(l)
Pure Substances
Elements Molecules & Compoundscan’t be broken
into simpler substances by ordinary
phys or chem. means
atoms of 2 or more different
elements chemically combinedbroken into
metals, metalloids, nonmetals, noble gases
salt, CO2, H2O, sugar
118 known elements! Ex. gold, silver, oxygen,helium
Mixtures
Homogeneous Mixture
Heterogeneous Mixture
Solutions
mixed uniformly, same
throughout
NOT mixed uniformly, NOT same throughout
solute – is dissolved
solvent – does dissolving
Colloids Suspensions
salt water pop
Kool-Aid
0.01 – 1 nm particles
1 - 1000 nm particles particles over 1000 nm
Scatter light “Tyndall effect”
latex paint Jell-O
mayonnaise detergent
butter
can filter, settle out
orange juice muddy water
Can’t filter, take a very long time to
settle out
Pure Substances
Elements
Compounds
Heterogeneous Mixtures
• Colloids– Particles too small to settle out
• 1 – 100 nm• Particles pass through ordinary filters (can’t be filtered)
– Examples• Latex paint, Jell-O, plasma, • Whipped cream, marshmallows, fog, smoke• Emulsions
– Mayo, cream, fats in small intestine
– Scatter light – called Tyndall effect
Heterogeneous Mixtures
• Suspensions• Particles eventually settle out
• May be filtered
• Examples– Muddy water, tomato juice, orange juice,
Classification of Matter
Solutions Colloids Suspensions
Homogeneous Heterogeneous Heterogeneous
Particle size:
0.01–1 nm
Particle size:
1–1000 nm
Particle size:
over 1000 nm
Do not separate on standing
Do not separate on standing
Particles settle out,
Shake before use.
Cannot be separated by filtration or membrane.
Cannot be separated by filtration. Only by
membrane
Can be separated by filtration or membrane.
Do not scatter lightScatter light
(Tyndall effect)May scatter light, but are not transparent
Classification of Matter
List an example of each below:
Element Zinc
Compound Carbon Dioxide
Solution Stained glass
Solid Mixture Granite
Suspensions Pulpy Orange Juice
Colloids Milk, Jell-O, Hair Spray
In one minute I will unveil possible answers.
Then we will be treated to a song feel free to sing a long.
Bell Work 11/10/11 – 5 minutes
1. What is the difference between a chemical change and a physical change?
2. Give 3 examples of chemical changes.
3. Give 3 examples of physical changes.
4. T/F Physical changes can always be “undone”.