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Lesson 9 NOTES: Physical and Chemical Properties and Changes (Unlock) Essential Question: -How do physical and chemical properties and changes help scientists to understand the world? Learning Target(s): -I can describe the physical and chemical properties and changes of matter I. Physical 1. Physical properties: __________ a. Ex: __________ 2. Physical change: __________ a. Ex: __________ 3. States of Matter *Read and take notes on the following: Phase" describes a physical state of matter. The key word to notice is physical. Things only move from one phase to another by physical means. If energy is added (like increasing the temperature) or if energy is taken away (like freezing something), you have created a physical change. When molecules move from one phase to another, they are still the same substance. There is water vapor above a pot of boiling water. That vapor (or gas) can condense and become a drop of water in the cooler air. If you put that liquid drop in the freezer, it would become a solid piece of ice. No matter what physical state it was in, it was always water. It always had the same chemical properties. On the other hand, a chemical change would build or break the chemical bonds in the water molecules. If you added a carbon (C) atom, you would have formaldehyde (H2CO). If you added an oxygen (O) atom, you would create hydrogen peroxide (H2O2). Neither new compound is anything like the original water molecule. Generally, changes in the physical state do not lead to any chemical change in molecules. **The melting and boiling points are not the same for all substances. How might these physical properties help to identify an unknown substance? II. Chemical 1. Chemical properties: __________ a. Ex: _____________ 2. Chemical change: change in identity due to chemical properties ------not reversible a. Ex: _____________ III. Law of Conservation of Matter: _______________________________ IV: Measuring Matter 1. Watch BrainPop video: "Measuring Matter" and take short notes 2. Read text "Mass, Volume, Density" and answer all questions in notebook **See pages 3-6 of this document

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Lesson 9 CLASSWORK: Physical and Chemical Properties and Changes Learning Target: I can describe the physical and chemical properties and changes of matter Vocabulary: physical; chemical Warm Up: Complete Socrative Assessment. Copy errors and confusions. Teaching: Review LT; Vocabulary; Socrative Results Possible Misconceptions: At solid state, molecules are closer together which increases density. The smaller something is, the less density it has. So smaller objects are less dense than larger objects. Task: 1. A. Develop a model that predicts and describes changes in the phase (state) of water when thermal energy

is added or removed to create a solid, liquid and gas. Describe changes in particle motion, temperature, energy, density, and annotate your model with the terms “melting point” and “boiling point.”

Use the following checklist to help evaluate your model: ___ Movement/Particle Motion is described ___ Temperature is described ___ Energy is described ___ Density is described ___ Melting Point is labeled ___ Boiling Point is labeled ___ The spacing of molecules is correct

B. Visit the following links to check your understanding: https://phet.colorado.edu/sims/html/states-of-matter-basics/latest/states-of-matter-basics_en.html https://www.khanacademy.org/science/biology/water-acids-and-bases/water-as-a-solid-liquid-and-gas/v/liquid-water-denser-than-solid-water-ice C. How have the simulation and video links changed your thinking? D. Respond to the following statements:

Liquid and gas molecules move but solid molecules do not. Solid molecules are more tightly packed than liquid or gas molecules.

2. "Case of the Missing Necklace” **See pages 7-8 of this document

3. "Cube Density- Sink or Float?" **See page 9 of this document Summarize: Check your answers

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Mass and Weight The mass of an object is the amount of matter it contains. A boulder has a large mass. A grain of sand has a small mass. In general, the more mass an object has, the heavier it feels. However, mass should not be confused with weight. Although the two terms are often used interchangeably, they are two different concepts.

Weight is the amount of the force of gravity between one object and another object such as Earth. The force of gravity between two objects depends on how much matter they contain and how far apart they are. The more matter an object contains, the stronger its gravity.

The mass of an object does not vary. It is the same everywhere in the universe. On the other hand, the weight of an object varies with its distance from the center of the Earth or any other planet or body on which it is measured. You weigh slightly more at sea level than you do on top of Mount Everest because you are closer to Earth’s center at sea level. However, your mass is the same in both places. On the Moon, you weigh about one-sixth what you weigh on Earth because the Moon has much less gravity than Earth. That does not mean that your body would be made up of one-sixth as much flesh, bone, and blood! Your body would contain the same amount of matter on the Moon as it does on Earth, that is, your mass would be the same.

On Earth, a box of cookies with a weight of 1 pound has a mass of 454 grams. If the box of cookies is taken to the Moon, which measurement would remain the same? Explain. __________________________________________________________________________________________ Measure: Mass Mass is the amount of matter in an object. Mass is measured using a balance. There are several different kinds of balances. Some balances give a single reading. Others give two or more readings that must be added to find the object’s total mass.

The balance on the right is a triple-beam balance. In this example, the middle beam measures the largest amounts. To find the mass of an object, record the masses on each of the beams. Then add the readings.

________________ g + ________________ g + ________________ g = ________________ _______________________________________________________________________________________________________________________________________

How would you find the mass of an object in a container? The mass of the container holding the table salt is 3 g. What is the mass of the table salt alone? _______________________

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Measure: Volume Volume is the amount of space the matter occupies. Volume can be calculated for regular objects, such as a suitcase, by using the following formula: Volume = Length x Width x Height. Because 3 numbers were multiplied, the unit of measure would be cubed (3).

When an object is submerged in water, it pushes water out of the way. If you measure the amount the water level increases, you can find the volume of the object. The graduated cylinder is a tool frequently used to measure liquid volume. Water in a graduated cylinder has a curved surface, as shown on the right. The curved surface is called a meniscus. The volume should be read at the lowest point of the meniscus. Be sure to read the volume at eye level. Always check the unnumbered marks on the graduated cylinder to see what each mark indicates. Sometimes, the bottom of the meniscus falls between two markings. In that case, you need to estimate the measurement between two marks. Both the graduated cylinders on the right contain the same volume of liquid. Although the cylinders have different markings, both cylinders contain 45 mL of liquid. __________________________________________________________________________________________ What is the volume of liquid shown in graduated cylinders 1-4 below? What is the total volume in graduated cylinder 5?

If the diagrams for 4 and 5 show the same graduated cylinder before and after the rock was added, what is the volume of the rock? ____________________ Explain the steps that you would use to determine the value of the unnumbered marks on a graduated cylinder.

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Calculate: Density The mass of a sample tells us how much we have but on its own it tells us nothing about what the sample is. Matter also has volume, and as the volume of a sample increases so does the mass. Density is an important physical property because items of the same substance will have the same density. Density is the measure of how closely the matter of a given substance is packed into a given volume. In other words, density is the mass (m) per unit volume (V) of a substance. For example, a 'gold' ring was found to have a mass of 5.9 g and a volume of 0.4 mL. The mass was measured using a balance, and the volume was measured by noting the increase in volume when the ring was placed into a measuring cylinder containing water. Density = 5.9 g / 0.4 mL = 14.8 g/mL Since the density of pure gold is 19.3 g/mL, we can conclude that the ring described above is not pure gold. Sinking or Floating? Suppose you have a block of wood and the block of iron of equal mass. When you drop both blocks into a tub of water, you see that the wood floats and the iron sinks. You know the density of water is 1 g/cm ³. Objects with densities greater than that of water will sink. Objects with lesser densities will float. Watch a bottle of oil and vinegar salad dressing after it has been shaken. You will see that the oil slowly forms a separate layer above the vinegar. This happens because oil is less dense than vinegar. Liquids can forms layers based on density. Use the information above to answer the following questions in your notebook. 1. Label the layers in the column according to their densities.

a. Water: 1.00 g/mL b. Corn syrup: 1.33 g/mL c. Honey: 1.36 g/mL d. Vegetable oil: 0.91 g/mL e. Dish soap: 1.03 g/mL

2. Calculate: What is the density of a liquid with a mass of 17.4 g and a

volume of 20 mL? Where would this liquid be in the column?

3. In which layer(s) would a solid cube with 6-cm sides and a mass of 270 g float? Explain.

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Review Questions: 1. What is mass?

2. How do you measure mass?

3. What is the difference between mass and weight?

4. Which object has a higher mass: a 20-gram brick or a 20-gram bag of feathers?

5. What is volume?

6. How do you measure volume using a graduated cylinder?

7. How do you measure volume using a ruler?

8. If you were measuring the volume of a cube, why would you only need to measure 1 side?

9. Which object has a higher volume: a 20-gram brick or a 20-gram bag of feathers?

10. What is density?

11. How do you measure or calculate density?

12. Which object has a higher density: a 20-gram brick or a 20-gram bag of feathers?

13. If the mass of a brick is 20 grams and the volume of a brick is 20 cm3. What is the density?

14. If I cut the same brick in half, what is the mass, volume, and density? Did the density of the brick change even

though the mass and volume changed?

15. Density asks you to consider 2 variables: mass and volume. Given the following data, determine the object with the greatest density without calculating.

a. Object 1: mass is 5 grams; volume is 50 cm3 Object 2: mass is 10 grams; volume is 50 cm3

b. Object 1: mass is 20 grams; volume is 100 cm3 Object 2: mass is 10 grams; volume is 100 cm3 c. Object 1: mass is 10 grams; volume is 50 cm3 Object 2: mass is 40 grams; volume is 60 cm3 d. Object 1: mass is 2 grams; volume is 50 cm3 Object 2: mass is 40 grams; volume is 60 cm3

16. Ball 1: Mass= 7 kg Volume= 6 liters

Ball 2: Mass= 1 kg Volume= 6 liters a. Which is ball 1 and which is ball 2? b. Describe how the physical properties of each ball compares. c. Suppose a beach ball is double the size of the one shown. How would the density change?

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TheCaseoftheMissingNecklace:CanyouSolvetheMYSTERY?LT:Icanusephysicalandchemicalpropertiesofmatterinordertoidentifyanunknownpowder.Amillionairenoticedherbelovedantiquepearlnecklacewasmissingfromherjewelrybox.CSI(CrimeSceneInvestigation)wascalledouttofindcluesthatmightprovewhostolethenecklace.Evidence:Aftersearchingthesceneofthecrime,investigatorsfoundsomemysteriouswhitepowderonthejewelrybox.Throughfurtherinvestigation,newevidencewasuncoveredandfoursuspectsweredetermined,allofwhichwerethemillionaire’spersonalemployees.Eachemployeeisknowntobeunhappyintheirworkconditionsandfrequentlyusesaspecificwhitepowder.

TheFarmerFarmerBobraisescorntocreatecornstarchforthemillionaire.Thecornstarchisusedforcookingbythechefandtheremainderissoldtomakemoneythatthemillionairealwaysspendsonherself.FarmerBobissickofthemillionaire’sselfishways.CouldthecornstarchFarmerBobmakesbethepowderfoundonthejewelrybox?

ThePersonalChefChefJoehasbeenpreparingmealsforthemillionaireforafewyearsnow.Themillionaire’sfavoritechocolatecakerequiresALOTofbakingpowder.ChefJoeissickofmakingthesamechocolatecakeandwantstoshowhisskillsmakingnewmeals,butthemillionairewillnotlethim.CouldthebakingpowderthatChefJoehastousebethepowderfoundonthejewelrybox?

TheScientistScientistAmyisstudyingbakingsodaforthemillionaire.Themillionairewantsthescientisttomakeabigdiscoverysothatthemillionairecanstealallthecredit.ScientistAmythinksbakingsodaisnotthatexcitingandwouldlovetoresearchsomethingelse,butthebossymillionairewillnotlether.CouldthebakingsodathatScientistAmyhastostudybethepowderfoundonthejewelrybox?

TheNannyNannyJantakescareofthemillionaire’sbabyboy.Ifthebabyboywasnotthesweetestlittleguyintheworld,NannyJanwouldhavequitherjobalongtimeago!NannyJanhastoworklonghoursandthemillionairedoesnotpayhernearlyenough!Beingananny,NannyJangoesthroughalotofbabypowder.CouldthebabypowderthatNannyJanusesfrequentlybethepowderfoundonthejewelrybox?

UsingyourCSIkit,youwilltestthefoursuspectpowders(cornstarch,bakingpowder,bakingsoda,andbabypowder)tolearntheirPhysicalandChemicalProperties.

Whenyoufinishtestingthefourpowders,repeatyourexperimentwiththeEvidencePowderfoundonthejewelrybox.YouwillthencomparethepropertiesoftheEvidencePowdertothefoursuspectpowderstofindonlyONEmatch.

It’syourjobtoclearthenamesofthethreeinnocentemployeesandputtheguiltythiefbehindbars!And,hopefullygetthemillionaire’sbelovedpearlnecklaceback!Participation I often contributed good ideas that were relevant to the topic and task. I came to meetings prepared. I did my share of the work.

4 3 2 1 I seldom contributed good ideas. Sometimes I was talking off-task. I did not come to meetings prepared. I did not do my share of the work.

Working with Others I often compromised and cooperated. I did take initiative when needed and/or listened and respected the ideas of others.

4 3 2 1 I seldom compromised and cooperated. I did not take initiative when needed and/or did not listen and respect the ideas of others.

Product My part of the task is complete and accurate. My work was submitted on time.

4 3 2 1 I did not complete my part of the task. The information I presented was inaccurate and/or not done correctly. It was not completed on time.

Understanding Content I can speak about the topic and group work knowledgeably. I can sum-up the lesson.

4 3 2 1 I do not understand what I did in my group. I did not ask or answer questions. I cannot sum-up the lesson.

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Name:_________________________________________Date:_____________________Class:________SubstanceSuspect

PhysicalPropertiesDescription

WaterReactionDescription

LitmusPaperDescription

VinegarReactionDescription

IodineReactionDescription

BakingSodaScientistAmy

AcidBase/AlkalineNeutral

FizzedNoReaction

StarchNoResult

CornstarchFarmerBob

AcidBase/AlkalineNeutral

FizzedNoReaction

StarchNoResult

BakingPowderChefJoe

AcidBase/AlkalineNeutral

FizzedNoReaction

StarchNoResult

BabyPowderNannyJan

AcidBase/AlkalineNeutral

FizzedNoReaction

StarchNoResult

EvidencePowderPrediction____________________________

AcidBase/AlkalineNeutral

FizzedNoReaction

StarchNoResult

Conclusion:Theanalysisoftheevidenceprovesthat_______________________________________________tookthenecklace.Icametothisconclusionbecause_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ 3 2 1LabDescription

Relevant,telling,qualitydetailsgivethereaderimportantinformationthatdescribesthelab.

Supportingdetailsandinformationarerelevant,butonekeyissueorportionisnotdescribed.

Supportingdetailsandinformationarerelevant,butseveralkeyissuesorportionsnotdescribed.Thereisaneedformoresupportingdetails.

DataTable Alldataisrecordedaccuratelyandpreciselywithnoerrors.

Mostdataisrecordedaccuratelyandpreciselywithnomorethan2errors.

Littledataisrecordedaccuratelyandpreciselywith3ormoreerrors.

Conclusion Conclusionisthoroughandusesspecificevidencefrombackgroundinformationanddata.

Conclusionisgeneralandusessomeevidencefrombackgroundinformationanddata.

Conclusionisgeneralandusessomeevidencefrombackgroundtextordata.

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Cube Density- Sink or Float? LT: I can determine properties of cube samples in order to predict how they would behave if they were placed in water. Facts: Volume = Length x Width x Height

Density = Mass/Volume

The density of water is 1.0g/cm3.

Use the data table below to record your data for the given cubes. Based on your calculations, determine if the cube would sink or float in water.

Cube Mass (g) *to the nearest tenth

Volume (cm3) *to the nearest 0.1 cm

Density (g/cm3) *to the nearest 0.1g/cm3

Sink or Float

A 37.0 g 50.7cm3 0.7 g/cm3 B C D E F G H I

Analyze Data to Draw Conclusions:

1. Notice that the density of Cube A has been provided in the data table (0.7 g/cm3). Assume block A was placed into the water. Draw a diagram that shows where you predict Cube A would be located in the container of water.

2. Which cubes are made of the same material? Explain how you know. 3. Which cubes seem to be made of the same material although are probably not?