Unit 4 – Properties of Matter

Physical Science Semester 2

2/2/15

• Entry Task

• Which elements do you think are most important for LIFE?

• HOMEWORK: Read pages 323-329 and 364-372. Answer #1-5 on p. 329 and #9-14 on p. 372. Due Thursday Feb 5, 2015.

• NEW HALL PASSES – stricter use: 5 passes each student. Ask permission, get my signature.

Elements of Life

• Elements of Life CHNOPS explained in “Hunting the Elements” https://www.youtube.com/watch?v=wsoZFTC02PY (1:03 – 1:20:30)

• CARBON and Radioactive decay explained in “Hunting the Elements” (1:39:30 – 1:44)

• ANSWER QUESTIONS from ½ sheet “Elements of Life” on the next LEFT side page of your comp book.

2/2/15

• Exit Task

• How many bonds connect each carbon atom to other elements in molecules?

• What kind of bonds are they?

• Why is carbon called the backbone of living things?

2/3/15

• Entry Task

• Write down what you know about the following molecules:

– Carbohydrates

– Lipids

– Proteins

– DNA/RNA

Today’s Agenda

• Take notes on BIOGEOCHEMICAL CYCLES – in other words, how elements are cycled between living and non-living things…

Biogeochemical cycles

• Biogeochemical cycles: how ELEMENTS move through living (biotic) to nonliving (abiotic) things and back again. – Abiotic examples: water, atmospheric gases – Biotic examples: plants and animals, food

• Elements included in these cycles are: – Carbon – Hydrogen – Nitrogen – Oxygen – Phosphorous – Sulfur

• These may also be called nutrients because they are needed for life

Macromolecules contain CHNOPS • LIFE needs Carbon. • Carbon forms four covalent

bonds to make large molecules:

• Carbohydrates: – Function is to store chemical

energy in bonds – made of simple sugars (rings)like

glucose (important in photosynthesis and cellular respiration)

• Lipids: – fats, etc. – One place they are found is the

cell membrane – Function of cell membrane is to

let things in or keep things out of cell.

Macromolecules contain CHNOPS • Nitrogen is very important

in the following BIOLOGICAL molecules…

• Proteins- 5 types by function: 1. Antibody

2. Enzymes

3. Messenger (hormones)

4. Structural

5. Transport/storage

• Nucleic Acids – DNA & RNA – Function is to carry genetic

information and contains the code to build proteins.

15.1 The carbon cycle

• Cycles carbon through the ecosystem

• Include the opposite chemical reactions:

• photosynthesis and cellular respiration

CARBON containing MOLECULES

Atmosphere holds ___________________

COMBUSTION of fossil fuels release ___________________

Example fossil fuel: ___________________

products __________ + ____________

reactants __________ + ____________

reactants __________ + ____________

products __________ + ____________

CARBON containing MOLECULES

Atmosphere holds _________ CO2 ______

COMBUSTION of fossil fuels release __________ CO2 _____

Example fossil fuel: COAL, methane, gas

Products C6H12O6 + O2

reactants CO2 + H2O

reactants C6H12O6 + O2

products CO2 + H2O

Photosynthesis and the atmosphere

• Photosynthesis in plant cells converts carbon dioxide and water to oxygen and glucose in a process that allows living things to use the sun’s energy.

http://www.phschool.com/science/biology_place/biocoach/photosynth/overview.html

6 H2O + 6 CO2 → C6H12O6 + 6O2

Cellular Respiration and the atmosphere

• Cellular respiration in plant AND animal cells breaks down glucose using oxygen into carbon dioxide and water in a process that allows cells to get energy out of their food.

• IT IS THE OPPOSITE CHEMICAL REACTION OF PHOTOSYNTHESIS

C6H12O6 + 6O2 → 6 H2O + 6 CO2

Nitrogen Cycle • Nitrogen Fixing Bacteria

in the soil take NITROGEN from the atmosphere and transfer it to plants.

• Animals eat plants or other animals which gets NITROGEN in their bodies to build PROTEINS or DNA/RNA.

• Other bacteria DENITRIFYING bacteria return NITROGEN to the atmosphere from decomposing matter

How does NITROGEN get from place to place? Atmosphere holds ___________________

___________________ Take nitrogen from the atmosphere and make it available to ___________________

Nitrogen then enters the plants through the ___________________

Nitrogen enters animals when they eat ___________________

Nitrogen leaves animals via ___________________

___________________ Return nitrogen to the atmosphere.

How does NITROGEN get from place to place? Atmosphere holds ______N2_____

NITRIFYING BACTERIA in soil Take nitrogen from the atmosphere and make it available to PLANTS

Nitrogen then enters the plants via ROOTS

Nitrogen enters animals when they eat PLANTS OR ANIMALS

Nitrogen leaves animals via WASTE or DECOMPOSITION

DENITRIFYING BACTERA in soil Return nitrogen to the atmosphere.

2/3/15

• Exit Task

• Briefly explain how CARBON cycles on planet earth. Use the words ATMOSPHERE, PLANTS, ANIMALS.

2/4/15

• Entry Task

• Can you think of a way to change the rate of a chemical reaction?

• For example, how could you change the rate of photosynthesis?

• Finish notes

• Do a computer simulation

6 H2O + 6 CO2 → C6H12O6 + 6O2

Today’s Agenda

Find the following link on my website: • SIMULATIONS for rates of chemical reactions:

http://mw.concord.org/nextgen/#interactives/chemistry/chemical-reactions/what-chemical-reaction

• Then click “interactives” • Under chemistry/chemical reactions, you will

complete the top 3 bullets • Under phase changes, you will complete the top

3 bullets.

Analysis Q for Simulations of Chemical Reactions • CHEMICAL REACTIONS(top 3 bullets): adjust # of atoms, concentration,

temperature

1. How did heating/cooling the container affect the kinetic energy of the particles? Temperature?

2. How does increasing the concentration of atoms affect the rate of reaction?

3. What are the best ways to ensure completion of reaction?

4. If you only add 2 atoms, describe the rate of reaction. Was it complete?

5. Play the chemical reaction at “low,” “medium,” and “high,” temperatures. Compare them. How does temperature affect rates of reaction?

• PHASE CHANGES(top 3 bullets): Mark 2 atoms and play. You may also “show attractions”

1. Describe the motion of atoms, relative to each other and the container, in the gas phase.

2. Describe the motion of atoms, relative to each other and the container, in the liquid phase.

3. Describe the motion of atoms, relative to each other and the container, in the solid phase

Analysis Q for Simulations of Chemical Reactions • CHEMICAL REACTIONS(top 3 bullets): adjust # of atoms, concentration,

temperature

1. How did heating/cooling the container affect the kinetic energy of the particles? Temperature?

2. How does increasing the concentration of atoms affect the rate of reaction?

3. What are the best ways to ensure completion of reaction?

4. If you only add 2 atoms, describe the rate of reaction. Was it complete?

5. Play the chemical reaction at “low,” “medium,” and “high,” temperatures. Compare them. How does temperature affect rates of reaction?

• PHASE CHANGES(top 3 bullets): Mark 2 atoms and play. You may also “show attractions”

1. Describe the motion of atoms, relative to each other and the container, in the gas phase.

2. Describe the motion of atoms, relative to each other and the container, in the liquid phase.

3. Describe the motion of atoms, relative to each other and the container, in the solid phase

2/4/15

• Exit Task

• Briefly explain how NITROGEN cycles on planet earth. Use the words ATMOSPHERE, NITRIFYING BACTERIA, PLANTS, ANIMALS, DENITRIFYING BACTERIA.

2/5/15

• Entry Task

• What would dissolve faster, salt in cold water or hot water? Why?

• What would dissolve faster, a sugar cube or granulated sugar? Why?

• Are the above physical or chemical changes?

• Can you relate these ideas to chemical changes?

• HOMEWORK EXTENDED due TOMORROW!

Today’s Agenda

• First 15 minutes - Finish simulation on laptops.

• Write down pre-lab info

Today’s Agenda

• STANDARD: I can predict the effect of a change in temperature, surface area, or pressure on the rate of a given physical or chemical change.

• GOAL for Thursday: Design a lab to test temperature change or change in particle size on rate of chemical change.

• GOAL for Friday: Design a lab to test exposed surface area on rate of chemical change.

•

“Temperature vs Rate of Reaction Lab”

• Question

– How does temperature affect the time it takes for Alka Seltzer® to react with the 15 ml of water?

• Have 3 different conditions for the independent variable (manipulated).

– Temperature- three different temperatures

• Write a Hypothesis

• Materials: Alka Seltzer, 15 mL water, beaker, thermometer, stop watch, hot plate

Procedure

1. Gather materials and put on goggles.

2. Put 15 mL of room temperature water in the beaker.

3. Put one half tablet of alka seltzer in beaker.

4. Start stopwatch moment of dropping alka seltzer in water and stop once it stops fizzing.

5. Record the total reaction times in data table

6. Repeat steps 2-5 two more times for 3 trials.

7. Repeat steps 2-6 but use ice water, 30 degrees and 60 degrees

8. Calculate and record average times.

Alka Seltzer Data Table

CONDITION TIME to COMPLETE REACTION in SECONDS (3 trials)

Average

Experimental Control Condition (room temp)

Condition 1 (ice water)

Condition 2 (30 degrees)

Condition 3 (60 degrees)

This chemical reaction…

• C6H8O7 + 3NaHCO3 → 3H2O + 3CO2 + Na3C6H5O7

• REACTANTS: sodium bicarbonate + citric acid --->

• PRODUCTS: water + carbon dioxide + sodium citrate

• You will write a CONCLUSION after the lab.

2/5/15

• Exit Task

• Identify the independent variable and the dependent variable in this investigation.

• What is your experimental control condition?

2/6/15

• Entry Task

• Say Something Nice

• Trade and grade HOMEWORK.

Today’s Agenda

• Conduct the 3 trials, at your team’s assigned temperature.

• Find 3 other teams who have the rest of the data you need.

• Write your conclusion.

2/6/15

• Exit Task

• Trade and Grade

2/9/15

• Entry Task

• Look at the following image. Although these have the same VOLUME, which side (right or left) has more EXPOSED SURFACE AREA?

Today’s Agenda

• Spend 5 minutes – completing all data tables for Temperature vs Reaction Time Lab.

• Conclusions are homework. Use RADDSS

• Write pre-lab information.

• Write YOUR OWN – Hypothesis

– Procedure

– data table

• CONDUCT THE LAB

“Exposed Surface Area vs Rate of Reaction Lab” • Question

– How does exposed surface area affect the time it takes for Alka Seltzer® to react?

• Have 3 different conditions for the independent variable (manipulated). – Exposed surface area: one-half tablet (least S.A.), 2

quarters (medium S.A.), one-half crushed (most S.A.)

• Write your Hypothesis • Materials: Alka Seltzer, 15 mL water, beaker, stop

watch, graduated cylinder, mortar and pestle • Write a procedure. Be sure to consult your

rubric. This lab is worth 30 points! • Create a data table.

“Exposed Surface Area vs Rate of Reaction Lab” • Question

– How does exposed surface area affect the time it takes for Alka Seltzer® to react?

• Have 3 different conditions for the independent variable (manipulated). – Exposed surface area: one-half tablet (least S.A.), 2

quarters (medium S.A.), one-half crushed (most S.A.)

• Write your Hypothesis • Materials: Alka Seltzer, 15 mL water, beaker, stop

watch, graduated cylinder, mortar and pestle • Write a procedure. Be sure to consult your

rubric. This lab is worth 30 points! • Create a data table.

2/9/15

• Exit Task

• List 2 controlled variables for this lab.

2/10/15

• Entry Task

• What evidence do you have of a CHEMICAL REACTION?

• What kind of graph would you use to present this data? Why?

• What will go on the X-axis? The Y-axis?

Today’s Agenda

• Finish Exposed Surface Area Lab

• Find the 2 other teams with the data you need.

• Sit down and work on your lab write-up: including GRAPH and CONCLUSION.

• Please call over Ms. M or a para to GRADE you when finished.

2/10/15

• Exit Task

• What can you conclude? Write your conclusive statement. In other words, write your “R.A.” (restate/answer) here.

• HOMEWORK: complete bar graph and write conclusions

2/11/15

• Entry Task

• Is radioactive decay, such as the transformation of Carbon 14 into Nitrogen 14, a physical, chemical or nuclear reaction? Explain your reasoning.

• REMINDER – The rest of the “Exposed S.A. vs Rate of Reaction Lab” is HOMEWORK

Today’s Agenda

• SHORT notes on fusion, fission, and radioactive decay.

• Conduct activity to generate a decay curve.

• Answer questions at end.

Nuclear Reactions

Fusion, Fission and Radioactive Decay

• Nuclear fusion is the process of combining the nuclei of lighter atoms to make heavier atoms.

14.4 Fusion

14.4 Nuclear Fission

• Nuclear fission is the process of splitting the nucleus of an atom.

• Examples are nuclear bombs or radioactive decay.

14.4 Radioactive Decay is spontaneous fission

• radioactive decay results in an unstable, radioactive isotope like carbon-14 becoming the more stable isotope nitrogen-14.

Radioactive Dating

• Process used to figure out the age of objects by measuring the amount of radioactive material remaining.

• Understanding radioactive decay of uranium-238 has allowed scientists to determine that the age of Earth is 4.6 billion years old.

Half-Life

• A half-life is the amount of time for half of the radioactive element to decay.

• As a radioactive element decays, it emits harmful radiation such as alpha and beta particles and gamma rays.

Understanding Decay Curves

• Title of Graph: “Uranium Decay Curve” • Y axis: Amount of U-238 left in sample. • X-axis: TIME in Half-lives (20 seconds each) • Starting Length of licorice represents the amount of U-

238 in the sample today. Mark the length on your graph paper.

• HALF-LIFE: 20 seconds. At the end of each half-life, break the licorice in half. Mark the new length on your decay curve.

• This shows that in every half-life, half of the remaining U-238 decays to Pb-209 or other atoms.

• Complete 6 half lives. • Radioactive by Imagine Dragons

Questions

• After one half-life, how much of the original licorice is left? Thus, how much U-238 was left?

• What happened to the other U-238 atoms? • Each time U-238 emits particles from its nucleus, it

turns into an element with less mass in the nucleus. Does this violate conservation of mass?

• If you found a sample with ¼ a stick of licorice, in other words, ¼ U-238 remaining, how old would it be in seconds?

• CHALLENGE: Scientists find a rock that is 1/8 U-238. They know the half-life of U-238 is 4.5 billion years. How old is the rock? Is the rock from earth or a meteor?

Questions

• After one half-life, how much of the original licorice is left? Thus, how much U-238 was left?

• What happened to the other U-238 atoms? • Each time U-238 emits particles from its nucleus, it

turns into an element with less mass in the nucleus. Does this violate conservation of mass?

• If you found a sample with ¼ a stick of licorice, in other words, ¼ U-238 remaining, how old would it be in seconds?

• CHALLENGE: Scientists find a rock that is 1/8 U-238. They know the half-life of U-238 is 4.5 billion years. How old is the rock? Is the rock from earth or a meteor?

2/11/15

• Exit Task

• Would you classify radioactive decay as nuclear fusion or fission? Why?

2/12/15

• Entry Task

• Define exothermic.

• Define endothermic.

• Can you think of a common example for each?

ANSWERS – you can show students

• Endothermic reactions are chemical reactions that release more energy than it uses

• Exothermic reactions are chemical reactions the use more energy than it releases

• EXAMPLES – see page 348 in textbook.

• Combustion of wood is exothermic.

• Photosynthesis is endothermic.

Today’s Agenda

• Read pages 348-350 and answer # 1-5 on page 353.

• Read pages 354-358 and answer #1,3,5,6,8,9 on page 359.

• Finish as HOMEWORK for tomorrow if you do not complete in class.

• Watch minutes 1:46 – 1:51 on “Hunting the Elements” (on disc or https://www.youtube.com/watch?v=wsoZFTC02PY )

2/12/15

• Exit Task

• Label the following as RELEASE ENERGY or ABSORB ENERGY

• Endothermic

• Exothermic

• Nuclear Fusion

• Nuclear Fission

ANSWERS – DO NOT show students

• Label the following as RELEASE ENERGY or ABSORB ENERGY

• Endothermic – absorb energy

• Exothermic – release energy

• Nuclear Fusion – release energy

• Nuclear Fission – release energy

2/13/15

• Entry Task

• Say Something Nice

• Assignment from yesterday’s class due WEDNESDAY.

Materials • test tubes, NH4Cl, water • balance • data collectors and temperature probe • graduated cylinder

Procedure 1. In test tube, add about 4 g of NH4Cl first and then

about 5 ml of water. 2. In data collector choose “meter mode” from home

screen to show Celsius vs Time. 3. Gently mix using temperature probe and record the

lowest temperature the solution reaches. 4. Make qualitative observations. 5. Rinse down drain.

NH4Cl(s) + H2O(l) + energy--> NH4

+(aq) + Cl-(aq) + H2O(l)

Observe an Endothermic Reaction

Watch video re. the exothermic reaction

between sugar and a strong acid.

Endothermic:

Describe the effect of this chemical reaction on

the temperature of the solution.

Which side of the equation includes the input of

energy?

Why would an absorption of energy “feel” cold?

Describe one other endothermic example.

Exothermic:

Is energy released or absorbed in this chemical

reaction?

If you touched the container, would it feel hot or

cold? Why?

Describe one other exothermic example.

2/13/15

• Exit Task

• Trade and Grade

2/18/15

• Entry Task

• What do you know about pH? Explain as many things that you can think of…

• Trade and Grade last Thursday’s assignment

Today’s Agenda

• Review Endo/Exothermic Q/A

• pH notes and demo

pH NOTES: Acids and Bases

• Acid: Substance that donates Hydrogen ions (H+) to a solution.

• Base: Substance that donates hydroxide ions (OH-) to a solution.

Water is Both an Acid and A Base

H2O H+ + OH-

Water hydrogen ion + hydroxide ion

pH Measurements

• pH or “potential hydrogen” measures how acidic or basic a solution is.

• The pH scale ranges from 0 to 14 • 0 < 7 = acid; the lower the # the stronger the acid.

• 7 = neutral: pure water

• >7 – 14 = basic; the higher the # the stronger the base.

Effects of adding acid or base to a solution

• What will happen if we add more drops of acid to a solution? How will the pH change?

• Let’s see!

• Sketch the graph that you observe.

• What will happen if we add more drops of base to a solution? How will the pH change?

• Let’s see!

• Sketch the graph that you observe.

Indicators can tell us the approximate pH of a solution

Litmus Indicator Paper

2/18/15

• Exit Task

• Complete these statements:

• A lower pH means…

• A higher pH means…

2/19/15

• Entry Task

• Topics for QUIZ: – Carbon containing molecules: Carbohydrates, Proteins, Lipids, Nucleic

Acids AND Biogeochemical Cycles – Chemical Reactions of importance to humans – Difference between physical, chemical, nuclear reactions – S.A. or Temp vs Rate of Reaction – Radioactive Decay Curves – Fission and Fusion – pH

• What do you know the best? • What do you know the least?

Today’s Agenda

• pH notes and demo

• Study Guide

What is the half life of Carbon 14?

If ¼ is left, how many half-lives have gone by?

After approximately 11,000 years, how much of the sample is still radioactive?

After approximately 17,200 years, how much of the sample is still radioactive?

2/19/15

• Exit Task

• What will you study tonight?

• How will you study? Which studying methods?

• Where will you study?

• REMINDER: tutoring M-Th in I-2. Need help? Go to tutoring today!!

2/20/15

• Entry Task

• First TEN MINUTES – Q/A about QUIZ. • Take QUIZ. • Prepare for Quiz.

• IF TIME AFTER QUIZ - Say Something Nice

• Please turn in your entry/exit task sheets for the week!

2/23/15

• Entry Task

• How do you determine density of an object?

• What two characteristics do you need to know about the object?

• If time: How could you measure those for an irregular solid?

Properties of Matter

Solid, liquid, gas

Density

Pure Substances and Mixtures

Phases of Matter • On Earth, pure

substances are usually found as solids, liquids, or gases or the phases of matter, or state of matter.

Melting and Boiling Point

The temperature at which a liquid becomes a gas is called the boiling point.

The temperature at which a liquid freezes or solid melts is called the melting point.

Materials can be identified by their melting and boiling points.

Graph of Phase Changes

Density is the mass per unit volume.

• Density is the mass per unit volume of a solid, liquid or gas – For liquids use units g/mL

– For solids use units g/cm3 or kg/m3.

• Density of a material is the same no matter the size, shape or quantity.

Density of common materials • The density of water is about one gram per cubic centimeter.

Density = mass/volume

1. Mass is measured with a balance or scale.

2. Use the displacement method or calculate the volume.

Example problem

• A piece of lead has a mass of 56.4 g and a

volume of 5 mL. Calculate its density.

ml is same as cm3 so sometimes see g/cm3

Looking for:

Solution:

Given:

Formula:

Density

Mass = 56.4 g Volume = 5 mL

D = m/v

D = 56.4 g/ 5 mL D = 11.28 g/mL Same as… D = 11.28 g/cm3

• Exit Task

• A solid wax candle has a volume of 1,700 mL.

• The candle has a mass of 1,500 g.

• What is the density of the candle?

FORMULA: D = m/V

Solution:

1,500 g ÷ 1,700 mL = 0.88 g/mL

2/23/15

2/24/15

• Entry Task

• Write down the definition of SOLUTION from the textbook.

• Is a solution a MIXTURE or a PURE SUBSTANCE?

• Can you think of a common solution you like to drink?

• List physical means of separation (p. 181).

• MAKE-UP QUIZZES DURING LATE START IN D-8!

Matter

Mixture Pure Substance

YES NO

YES NO

Homogeneous

Mixture Heterogeneous

Mixture

NO

Element Compounds

or Molecules

Are the particles one

kind of atom?

Are all the particles alike?

Are the particles well-mixed

and mixed evenly?

YES

Classifying Matter – pure substance

or mixture?

POP QUIZ:

Pure Element,

Compound/Molecule,

or Mixture?

1. Heterogeneous Mixture

– different samples are not necessarily made up of exactly the same proportions of matter

– can often see different particles mixed together

– often can be easily separated

Mixtures

2. Homogeneous Mixture

– is the same throughout

– often can’t see different particles mixed together

– often difficult to separate

– examples: steel, milk, salt water, Kool Aid®

What is a solution?

• Solution: A mixture that is homogeneous down to the molecular level

Example:

think Kool-Aid…

Types of solutions

• 2 solids – metal alloy like steel

• 2 liquids – lemon juice and water

• Solid and liquid – salt water

• Liquid and gas – carbonated drink

• Gas in gas – oxygen and nitrogen in atmosphere

Parts of a solution

• Solvent : the thing that does the dissolving.

(the water)

• Solute : the thing that gets dissolved.

(the Kool-Aid powder)

• Could you filter out the powder after it dissolves?

• No, it is homogeneous to the molecular level.

How could you get the dissolved solid back out of solution?

• Evaporation or boiling! Remove all the liquid by turning it into a gas and the solid will recrystallize.

• Boil off the liquid at a low temp and keep the solid before it reaches its melting point!

• Liquid turns to gas… solid is left behind!

• DEMO

• http://www.youtube.com/watch?v=O87PYJgiw1Y

Separation of a Solution: Dissolved Solid and Water

• Question – How can we separate and identify the dissolved solid?

• Materials – 50 mL Beaker

– Ceramic crucible

– Graduated cylinder

– balance/scale

– Soluble solid

– hot plate

– Lab scoop

– safety goggles

– Rubbing alcohol

– Plastic dish

• Procedure and Data

– Measure 3 g. of the solid

– Measure 20 mL of water

– Add both the solid and water to the small beaker and stir over

until dissolved.

– Pour solution into crucible. Boil off the liquid at a medium-

high temp, reserving the solid before it reaches its melting

point!

– When the solid is recrystallized, scrape it into weighing dish.

– Measure mass on digital balance

– Record the physical characteristics: Ex. solid, crystalline,

metallic, etc

– Measure volume by displacement in alcohol.

– Calculate density (D=mass/volume)

– Conduct a flame test for color when burning.

Data Collection

Physical Properties – phase at room temp, color, texture, brittle or ductile

Mass Volume DENSITY = mass/volume

Flame Test for color

Analysis and Conclusion

• What evidence do you have that the substance dissolved in water versus reacted with the water?

• What is the solvent and what is the solute in this investigation?

• Explain how you separated the dissolved solid from the water.

• Consult Sludge Matrix. • Based on the evidence, can you infer what the dissolved

solid is? • Make a claim using evidence for support. • Use as many pieces of evidence/data from your lab as you

can.

2/24/15

• Exit Task

• In Portugal, they allow salt water to pour into shallow pools. After a number of days in the hot sun, the sea salt can be collected from the edges of the pool.

• How is the solid salt separated from the sea water?

2/25/15

• Entry Task

• Consider salt (NaCl) in water.

• Would this be a chemical or physical change?

• What evidence do you have?

• Consider CaCl2 and water.

• Chemical or Physical? Evidence?

• LAST QUESTION: How is dissolving different than melting?

Today’s Agenda

• Finish writing down pre-lab – 10 min

• Follow your procedure carefully!

• Come over to my desk/fume hood area to do the mass and volume tests.

• We will do the flame test tomorrow!

• LAST 5 – careful clean-up

2/25/15

• Exit Task – CANCELLED! Due to lab clean-up

• Consult the sludge matrix.

• If I showed you a crystalline, white soluble solid with density of 0.8 g/mL and flame color red/orange. What do you think it is?

2/26/15

• Entry Task

• Look at your safety rules (Unit 1 – front of binder).

• Write down 3 safety rules for using Bunsen burners or open flames in the lab.

• HW: Read pages 178-182, #1-5 p. 183.

• Read pages 190-194, #1-6 p. 195.

• Read pages 534, 536, 538-539, #1-5 p. 545.

• DUE MONDAY 3/2/15

Today’s Agenda

• Finish Dissolved Solid Lab • Copy Data Table. • Find mass on balance on Ms Maring’s desk. • Find volume by displacement in alcohol inside

fume hood. • Watch flame test demo. • Wait for supervisor! • Conduct flame test – hair and loose clothing tied

back. • Finish Analysis and Conclusion.

2/26/15

• Exit Task

• Which substances do you think the white soluble solid could be? Why?

• Make a claim and back it up with evidence!

2/27/15

• Entry Task

• Say Something Nice

Learn about Bunsen Burners

• What is a Bunsen Burner - history

• Video Tutorial – the one minute version

• Slow down! – How to Light a Bunsen Burner

• Notes – parts and steps of use

• Monday you will take a quiz and a performance assessment on using Bunsen burners.

• You will have to pass the quiz and the performance assessment in order to get your Bunsen burner license.

• What is the right sequence?

Label the parts

• air intake

• combustion nozzle

• barrel/body tube

• gas jet (point to inside)

• base

• gas valve/dial

Label the parts

• air intake

• combustion nozzle

• barrel/body tube

• gas jet (point to inside)

• base

• gas valve/dial

Functions of Parts

– air intake: adjustable; controls amount of oxygen; adding more air makes flame hotter

– combustion nozzle: gas and air mix to ignite

– barrel: turn this to adjust air intake

– gas valve/dial: adjustable; controls amount of gas entering burner; adding more gas makes flame taller

– base: holds up Bunsen burner

– gas jet: small hole that gas goes through

Steps to Light and Turn Off 1. Wear safety goggles, tie back long hair, no loose clothing. 2. Check striker for sparks. 3. Attach hose to burner and gas line . 4. Turn barrel clockwise to close and then open slightly to let a small

amount of air flow. 5. Turn gas valve/dial counter clockwise to close. 6. Turn on gas by rotating valve parallel to hose. 7. Open gas valve/dial slightly – should hear faint hissing. 8. Hold striker at 45 degree angle and light. 9. For a taller flame – open gas valve/dial more to allow more gas. For a

shorter flame – turn gas valve/dial back counter clockwise. 10. For a hotter flame – turn barrel counter clockwise (increases air flow).

Flame should turn blue. 11. For a cooler flame – turn barrel clockwise (decreases air flow). Flame

should turn orange. 12. The ideal flame is pale blue with a darker blue core. Draw a picture of

the flame. 13. To turn off: turn barrel clockwise for a cooler, orange flame. Completely

turn off the gas valve/dial. Turn off gas line.

Safety Precautions

• Wear safety goggles, tie back long hair, no loose clothing.

• Hold Bunsen burner at the bottom to avoid burns.

• Never leave open flames unattended.

• Know location of safety exits, emergency shut-off and fire extinguishers.

2/27/15

• Exit Task

• Trade and Grade

• REMINDER – your homework is due Monday!

3/2/15

• Entry Task

• Fill in the blanks: 1. Attach hose to _______ and ________ . 2. Turn barrel _________ to close and then open slightly to

let a small amount of air flow. 3. Turn __________ _______-_______ to close. 4. turn on gas by rotating valve _________ to hose. 5. Open gas valve/dial slightly – should hear __________. 6. Hold _________ at 45 degree angle and light. TRADE AND GRADE HOMEWORK!!

Today’s Agenda

• Finish Bunsen Burner Notes

• Take Written portion of Bunsen Burner Quiz

• Extra time? Practice the steps of lighting Bunsen Burner AT YOUR DESKS (no GAS!!)

Functions of Parts (notes in comp books)

– air intake: adjustable; controls amount of oxygen; adding more air makes flame hotter

– combustion nozzle: gas and air mix to ignite

– barrel: turn this to adjust air intake

– gas valve/dial: adjustable; controls amount of gas entering burner; adding more gas makes flame taller

– base: holds up Bunsen burner

– gas jet: small hole that gas goes through

Steps to Light and Turn Off (notes in comp books)

1. Wear safety goggles, tie back long hair, no loose clothing. 2. Check striker for sparks. 3. Attach hose to burner and gas line . 4. Turn barrel clockwise to close and then open slightly to let a small

amount of air flow. 5. Turn gas valve/dial counter clockwise to close. 6. Turn on gas by rotating valve parallel to hose. 7. Open gas valve/dial slightly – should hear faint hissing. 8. Hold striker at 45 degree angle and light. 9. For a taller flame – open gas valve/dial more to allow more gas. For a

shorter flame – turn gas valve/dial back counter clockwise. 10. For a hotter flame – turn barrel counter clockwise (increases air flow).

Flame should turn blue. 11. For a cooler flame – turn barrel clockwise (decreases air flow). Flame

should turn orange. 12. The ideal flame is pale blue with a darker blue core. Draw a picture of

the flame. 13. To turn off: turn barrel clockwise for a cooler, orange flame. Completely

turn off the gas valve/dial. Turn off gas line.

Safety Precautions (notes in comp books)

• Wear safety goggles, tie back long hair, no loose clothing.

• Hold Bunsen burner at the bottom to avoid burns.

• Never leave open flames unattended.

• Know location of safety exits, emergency shut-off and fire extinguishers.

Today’s Agenda

• Finish Bunsen Burner Notes

• Take Written portion of Quiz

• Get back the Unit 4 Quiz

• If you need/want to do a reflection, complete now.

• If you don’t, practice the steps of lighting Bunsen Burner AT YOUR DESKS (no GAS!!)

3/2/15

• Exit Task

• Fill in the blanks:

• To turn off: turn barrel _________ for a cooler, orange flame. Completely turn off the __________. Turn off _________.

3/3/15

• Entry Task

• Describe how you would get a cool flame with the Bunsen burner. What color would it be?

• Describe how you would get a hot flame with the Bunsen burner. What color would it be?

• Describe how you would decrease the height of the flame.

Finish things from Monday…

• Study for the Bunsen Burner Quiz – 10 min • You can use the Bunsen burners at your desks to

study • Take Quiz 10-15 min • See next slide…for Tuesday • Get back the Unit 4 Quiz – review answers • If you need/want to do a reflection, complete

now. • If you don’t, practice the steps of lighting Bunsen

Burner AT YOUR DESKS (no GAS!!)

Today’s Agenda

• Get back the Unit 4 Quiz – review answers • If you need/want to do a reflection, complete now. • If you don’t, practice the steps of lighting Bunsen

Burner AT YOUR DESKS (no GAS!!) – PRACTICE:

• 1. Goggles and tie back hair. • 2. attach hoses • 3. allow a small amount of air • 4. Close gas valve/dial • 5. Turn on gas line. • 6. Turn on small amount of gas. • 7. Light with striker

• When you are ready, you can come to the front for the performance assessment.

3/3/15

• Exit Task

• What part of the Bunsen Burner flame is the hottest? Draw a picture or explain

• If you want to finish your reflection for Quiz 4, come to tutoring TUES, WED, THURS 2:30 – 3:30 or schedule with me

3/4/15

• Entry Task

• If you had 2 unknown liquids mixed together, how might you separate them?

• Once separated, what other tests could be run to determine their identities?

Today’s Agenda

• Discuss quiz answers. • Fix all circled or underlined items on your Bunsen Burner Quiz • Practice the steps of lighting Bunsen Burner AT YOUR DESKS (no

GAS!!) – PRACTICE:

• 1. Goggles and tie back hair. • 2. attach hoses • 3. allow a small amount of air • 4. Close gas valve/dial • 5. Turn on gas line. • 6. Turn on small amount of gas. • 7. Light with striker

• When you are ready, you can come to the front for the performance assessment. Bring your corrected written quiz so I can verify 100%!

• While waiting, answer #15-20 on page 196 AND #1-2 on page 197 AND #7-8 (Section 8.3) page 198.

Fractional Distillation

• Question

– How can a mixture of two liquids be

separated and identified?

• Materials

– fractional distillation apparatus

– 2 small test tubes, 1 large test tube, and rack

– 3 stoppers

– Boiling chips

– liquid mixture

– Bunsen burner/striker

Distillation is used in the petroleum industry

• Distillation Procedure – Get 15 ml of the liquid mixture (never fill the

test tube you are heating more than 1/3 full). – Make sure there are about 10 boiling chips in

the test tube you will be heating. – Heat with Bunsen burner on the LOWEST

HEAT POSSIBLE in order to maintain a mild, rapid boil.

– Carefully watch the temperature. – Keep the rubber tube out of the liquid you are

“making”. – AFTER the temperature has leveled off for a

while and BEFORE it begins to rise again– carefully switch test tubes to “catch” the second liquid.

– Conduct flammability test of each liquid. – Find mass and volume of each liquid at fume

hood. Calculate density.

Liquid Boiling Point

Physical Properties – phase at room temp, color, odor

Mass Volume DENSITY = 𝑚𝑎𝑠𝑠

𝑣𝑜𝑙𝑢𝑚𝑒

Flammable?

A

B

• A few demos Set up. Flammability test.

• In groups of 3, go to lab station – LABEL RACK WITH PERIOD and GROUP #

• Today: finish distillation.

• Label small test tubes (Liquid A or B) and leave in test tube rack on shelf for your class.

Analysis and Conclusion

• What did you observe about the temperature prior to each liquid boiling? During boiling?

• Explain how you separated the 2 liquids based on their different boiling points.

• Consult Sludge Matrix. • Based on the evidence, can you infer the identity

of each liquid? • Make a claim using evidence for support. • Use as many pieces of evidence/data from your

lab as you can

3/4/15

• Exit task

• Explain how you can use distillation (boiling and then cooling back to liquid) to separate liquids with different boiling points.

3/5/15

• Entry Task

• Explain how you will adjust the Bunsen burner for the coolest and shortest flame possible.

Today’s Agenda

• Finish licensing – YOU NEED TO BRING YOUR CORRECTED QUIZ WITH YOU!

• While waiting, answer #15-20 on page 196 AND #1-2 on page 197 AND #7-8 (Section 8.3) page 198.

• Pre-lab writing for Fractional Distillation Lab

• Demo of set-up

3/5/15

• Exit Task – identify the phase changes on this graph. How do you know?

A

C

B

3/6/15

• Entry Task

• Say Something Nice

Today’s Agenda

• If you do not have your license – DO NOT TOUCH the Bunsen Burners

• Write Pre-Lab

• Conduct Lab

• MONDAY - Finish Lab and Analysis/Conclusion

3/6/15

• Exit Task

• Trade and Grade

3/9/15

• Entry Task

• Once Liquid A is boiled off and thus the 2 liquids separated, why will you need to also boil off Liquid B?

Today’s Agenda

• Conduct Lab – Distill liquid A and B

– Conduct Flammability Test at front counter

– Find mass and volume for both liquids at Ms. Maring’s Desk/Fume Hood

• Complete Analysis/Conclusion Q/A

• Clean-up: let cool; rinse large tube, put boiling chips back in container; all materials back in tote

3/9/15

• Exit Task

• Make a claim for the identity of Liquid A.

• Make a claim for the identity of Liquid B.

• List 2 pieces of evidence for each.

3/10/15

• Entry Task

• Tomorrow you will get a mixture called Sludge.

• It will have liquids, a dissolved solid, and metallic solids.

• How and in what order would you separate these substances?

• List the tests you will perform to identify them.

Today’s Agenda

• Complete the flammability and mass/volume tests. • Complete your Distillation Analysis Q/A • WRITE DOWN THE FOLLOWING IN YOUR COMP BOOKS: • TITLE: HCl Acid Test and Melting Point Test 1. There are 5 solids on the front counter 2. Retrieve 3 pieces of 2 metals in weighing boats 3. Come to fume hood for HCl Acid reactivity test. 4. Go to front counter Bunsen Burners for melting point test. 5. Find mass with mass balance and volume by displacement

in small graduated cylinder. Calculate density. 6. ID your solids!

Solid Melting Point

Physical Properties – phase at room temp, color, odor

Mass Volume DENSITY = 𝑚𝑎𝑠𝑠

𝑣𝑜𝑙𝑢𝑚𝑒

React with Acid?

A

B

Melting Point Test

• 800 ºC

• 1000 ºC

• 400 ºC

3/10/15

• Exit Task

• If a solid shiny, silver, metallic substance has a melting point of approx. 800-1000; density of approx. 9.25 g/mL; and does not react with HCl acid…what would you think it is?

3/11/15

• Entry Task

• Describe how you will determine the approximate melting point of the metals.

Today’s Agenda

• Do the HCl and Melting Point Tests

• Review Sludge Materials

3/11/15

• Exit Task

• Make a claim for the identity of one of your metals.

• Include data from your lab and COMPARE TO SLUDGE MATRIX.

3/12/15

• Entry Task – new seating chart = SLUDGE GROUPS

• Write down your team mates names

• Write down you group #.

• Write down your SLUDGE # HERE AND

• Write your SLUDGE # on your RUBRIC.

Today’s Agenda

• Remove metallic solids from mixture.

• Test the metallic solids and record data.

• You should have all the testing complete on the metallic solids by exit task.

• Keep any remaining metal in separate weighing boats - mark with your Period, Group # and Sludge #

3/12/15

• Exit Task

• Make a claim for the identity of one of your metals.

• Include data from your lab and COMPARE TO SLUDGE MATRIX.

3/13/15

• Entry Task

• Say Something Nice

Today’s Agenda

• Separate the dissolved solid (out of 20 mL) by boiling.

• Test the dissolved solid and record data.

• You should have the separating complete and at least 1 test complete by exit task.

• Keep any remaining soluble solid in a weighing boat – mark with your Period, Group # and Sludge #

3/13/15

• Exit Task

• Trade and Grade

• Please turn in your entry/exit task sheets for the week.

3/16/15

• Entry Task

• Which tests will you need to complete on the soluble solid that you separated on Friday?

• Record the tests you did not have a chance to finish in your “notes” column.

Today’s Agenda

• Fractional Distillation of the liquids. • 3 people: 1. Flame – never leave unattended; always cool orange and

short 2. Thermometer – first time it stops for several minutes is

boiling point of A; second time it stops for several minutes is boiling point of B

3. Tubes/Distillate – do not let tube drag AND switch test when temperature starts rising AFTER liquid A is boiled off.

• Mark your test tubes A and B and store them in the blue racks on your shelf

• You will probably need to test your liquids on Tuesday.

3/16/15

• Exit Task

• Make a claim for one of your liquids.

• Support your claim with 2 pieces of evidence.

3/17/15

• Entry Task

• At this point, all substances should be separated.

• Review your data table, WRITE DOWN ALL TESTS YOU STILL NEED TO DO and ON WHICH SUBSTANCES.

Today’s Agenda

• First Priority: Testing on Liquids separated yesterday – flammability, density and react to acid.

• Next steps: any tests on other substances you have not completed.

• BE SURE YOUR HAVE ADULT SUPERVISION if conducting an acid reactivity, melting point, or flame color/flammability test.

3/17/15

• Exit Task

• Is distillation a chemical or physical process?

• Explain.

3/18/15

• Entry Task

• What will you do if some of your data does not match the Sludge Matrix?

• How will you draw the best conclusion?

Today’s Agenda

• Last day for ANY testing.

• Don’t forget to fill out your daily log for each day.

• Some teams will be ready to write conclusions.

• CONCLUSIONS: – 5 paragraphs – one for each substance

– You must include all data even if it conflicts with your conclusion

3/18/15

• Exit Task

• Describe ONE area of weakness over the last 5 days of your Sludge Lab. Be specific and use sentences.

3/19/15

• Entry Task

• What do you think is the coldest temperature in the universe?

• What would particles be “doing” at such low temperatures?

• NOTE: Brief pause in the SLUDGE program….to be continued tomorrow when Ms. M returns.

ANSWERS – read and discuss with students

• http://science.nasa.gov/science-news/science-at-nasa/2014/30jan_coldspot/

• “Jan. 30, 2014: Everyone knows that space is cold. In the vast gulf between stars and galaxies, the temperature of gaseous matter routinely drops to 3 degrees K, or 454 degrees below zero Fahrenheit.

• It’s about to get even colder. • NASA researchers are planning to create the coldest spot in the known

universe inside the International Space Station. • “We’re going to study matter at temperatures far colder than are found

naturally,” says Rob Thompson of JPL. He’s the Project Scientist for NASA’s Cold Atom Lab, an atomic ‘refrigerator’ slated for launch to the ISS in 2016. "We aim to push effective temperatures down to 100 pico-Kelvin.“”

• PARTICLES would be moving VERY slowly…hardly moving at all. “At such low temperatures, ordinary concepts of solid, liquid and gas are no longer relevant. Atoms interacting just above the threshold of zero energy create new forms of matter that are essentially ... quantum.”

Today’s Agenda

• Watch Absolute Zero

• Answer Movie Q

3/19/15

• Exit Task

• Why are scientists so intrigued with absolute zero?

3/20/15

• Entry Task

• Say Something Nice

Today’s Agenda

• Write conclusions for Sludge

• 5 paragraphs

• All data must be described.

• All data must be compared to Sludge Matrix.

• If you need help getting started, let me know and I can show you a model.

3/20/15

• Exit Task

• Trade and Grade