Voltage

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VoltageElectrochemical Batteries012-10740 r1.04

The Snapshot button is used to capture the screen. The Journal is where snapshots are stored and viewed.The Share button is used to export or print your journal to turn in your work.

IntroductionJournals and SnapshotsNote: You may want to take asnapshot of the first page ofthis lab as a cover page for your Journal.Each page of this lab that contains the symbol

should be inserted into your journal. After completing a lab page with the snapshot symbol, tap (in the upper right hand corner) to insert the page into your journal.

Electrochemical Batteries

2Lab ChallengesDetermine the components required to make a battery.List metals in order by the amount of voltage (energy per unit charge) they produce when used in a battery.Devices need energy to operateEnergy from the burning of gasoline. Energy from the electricity that runs through the wires and outlets in your house.Energy from batteries.Electrochemical Batteries

BackgroundThere are many types of energy. Energy can be classified as either kinetic energy or potential energy. Kinetic energy is energy in motion, while potential energy is energy that is stored (in various ways) until being released as kinetic energy.


...BackgroundElectricity has kinetic energy because it is the flow of electrons from one substance to another. Copper wire

A battery has potential energy because it stores chemicals which contain energy in their bonds (chemical energy). When the chemicals are allowed to react, electrons are transferred producing energy in the form of electricity.

Electrochemical BatteriesSelf-CheckElectricity is a form of _______________. static dischargepotential energycombustion energykinetic energyElectrochemical Batteries

L6 text box[ The best choice is (tap here to enter text) ] 6...BackgroundChemicals react in order to form new bonds that are lower in energy and thus more stable. Chemicals are the most stable when their valence electron shell is full. Sodium ionSodium atomMetallic atoms can lower their potential energy and become more stable by losing electrons to fill their outermost energy shell.The easier a metal loses its electrons the more reactive the metal is and the more energy it can produce. Electrochemical Batteries

NaNa++

Self-CheckWhat makes an atom stable?a full valence shellan equal number of protons and electronsan unequal number of protons and electronslosing electrons Electrochemical Batteries

+ L6 text box[ The best choice is ] 8

...BackgroundAn electrochemical battery (voltaic cell) is designed to take advantage of the relative abilities of metals to lose electrons.Two metals (electrodes) are physically separated from each other and are connected by a wire conductor. Each metal is surrounded by an electrolyte solution and the solutions are connected using a salt bridge which allows ions to flow between cells in order to balance the charges and complete the circuit. WireMetal #1Metal #2Salt bridgeElectrolyte solutionsElectrochemical Batteries...BackgroundAn equilibrium (balance) between the metal and its ion is established at each electrode depending on the ease with which the metal loses its electrons (a half-reaction). The greater the difference between the two metals' ability to lose electrons, the greater the difference in negative charge created between the two electrodes. This difference (potential difference) is measured as voltage (energy per unit charge). The greater the difference between the two metals the more energy per charge the battery can produce. Half-reaction(more active metal)Half-reaction(less active metal)Electrochemical Batteries

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Self-CheckWhat is voltage a measure of?flow of electronsenergy per unit chargelosing electronsreaction time Electrochemical Batteries

L6 text box[ The best choice is ]

11...BackgroundWhen the battery is switched on, the electrons move from the more active metal through the wire to the less active metal allowing the two half-reactions to occur simultaneously to produce energy.The more active metal loses electrons (oxidation) while the less active metal gains electrons (reduction). This type of chemical reaction is called a redox reaction.

Losing electronsGaining electronsElectrochemical Batteries

...BackgroundOn a battery, the two electrodes are differentiated from each other by marking one with a "+" the other with a "-".The metals and electrolytes used in a battery determine the voltage produced by the battery. Each different chemical reaction has a characteristic voltage.

1.5V Battery 9V Battery Electrochemical Batteries

SafetyFollow all common laboratory safety procedures.Beware of sharp edges on the metal electrodes.Do not eat any of the food used in this lab. Discard the fruit according to your teachers instructions. Wash your hands after handling chemicals, electrodes, equipment, and glassware.Electrochemical Batteries

Materials and EquipmentCollect all of these materials before beginning the lab.Voltage sensorAlligator clips, (1 black, 1 red) Beakers (2), 50-mLGraduated cylinder, 50-mLThick string or yarn, 20 cmWash bottle and waste containerKnife to cut fruitElectrochemical Batteries

waste

...Materials and EquipmentAlso collect these additional materials before starting. Copper stripZinc stripMagnesium stripTwo or more of the following metal strips: lead, iron, nickel, or tin0.1 M Sodium chloride solution, 5-10 mL0.1 M Hydrochloric acid, 50 mLLemon Tomato Na-ClElectrochemical Batteries

The steps to the left are part of the procedure for this lab activity. They are not in the right order. Determine the correct sequence of the steps, then take a snapshot of this page.Sequencing Challenge

A. Test the voltage of zinc, then replace zinc with three different metals and test the voltage. B. Replace the HCl with a lemon and then a tomato and find the voltage produced by each metal.C. Assemble the electrochemical battery using 0.1M HCl as the electrolyte and copper and zinc as the electrodes.D. Use the data collected to list the metals in order by the amount of voltage they produced when used in a battery. Electrochemical BatteriesL6 text box[ The correct sequence of steps is ] 17Setup: 0.1 M HClConnect the voltage probe directly to the data collection system. Connect the red alligator clip to the red voltage probe lead and connect the black alligator clip to the black voltage probe lead. Pour approximately 25 mL of 0.1 M hydrochloric acid (HCl) into each 50-mL beaker. The HCl is the electrolyte solution.Place a zinc strip in one beaker and a copper strip in the other. Note: Copper will be used in all the electrochemical cells as a reference to compare the other metals. Q1: What is an electrolyte solution? What makes this solution electrolytic? Electrochemical Batteries

L6 text box[ An electrolyte solution ] 18

Setup: 0.1 M HClWet a 20 cm piece of string with the 0.1 M sodium chloride solution and hang it between the two beakers with the ends submerged in the electrolyte solution. This is the salt bridge. Q2: Is it necessary to have a separate beaker for the copper strip and the zinc strip? Explain.Electrochemical Batteries

L6 text box[ The zinc and copper ] 19*To Enter Data into a Table: Tap to open the tool palette.Tap then tap a cell in the data table to highlight it in yellow.Tap to open the Keyboard screen.Setup: 0.1 M HClEnter the names of all the metals you will use with copper to create your electrochemical batteries. Start by entering "zinc" in row one (do not list copper)*Electrochemical Batteries

Table- metal20Collect Data: HClTap to start a data set. Attach the red lead to the copper strip and the black lead to zinc strip using the alligator clips. Tap to record the voltage (run 1: HCl).Replace the zinc strip with the next metal in your table. Tap to record the voltage. Repeat step 4 until the voltage of each metal has been recorded. Tap to stop the data set.Electrochemical Batteries

Table metal and voltage21Collect Data: HClQ3: What was the dependent variable and the independent variable in the experiment performed on the previous page? Electrochemical Batteries

L456 text box[ The dependent variable ] [ The independent variable ] 22Remove both metal strips from the beakers.Clean all the metal strips with water and dry them. Roll the lemon firmly on the tabletop with the palm of your hand. Use a knife to make two slits wide enough for the electrodes to be inserted about 2-3 cm apart from each other in the lemon.Insert the copper strip in one slit and the zinc strip in the other slit.

Q4: Is there an electrolyte solution in the lemon? Explain.Setup: LemonElectrochemical Batteries

L6 text box[ The lemon ] 23Collect Data: LemonTap to start a data set. This data set will be recorded in the 2nd voltage column. Attach the red lead to the copper strip and the black lead to zinc strip using the alligator clips.Tap to record the voltage (run 2: lemon). Replace the zinc strip with the next metal in the table. Tap to record the voltage. Repeat step 4 until the voltage of each metal has been recorded. Tap to stop the data set. Electrochemical Batteries

Table metal, voltage, and voltage24Setup: TomatoRemove both metal strips from the lemon.Clean all the metal strips with water and dry them. Use a knife to make two slits wide enough for the electrodes to be inserted about 2-3 cm apart from each other in the tomato.Insert the copper strip in one slit and the zinc strip in the other slit. Q5: What is voltage a measure of? Electrochemical Batteries

L6 text box[ Voltage measures ] 25Collect Data: TomatoTap to start a data set. This data set will be recorded in the third voltage column. Attach the red lead to the copper strip and the black lead to zinc strip using the alligator clips. Tap to record the voltage (run 3: tomato).Replace the zinc strip with the next metal in the table. Tap to record the voltage. Repeat step 4 until the voltage of each metal has been recorded. Tap to stop the data set. Electrochemical Batteries

Table: metal, voltage, voltage, voltage26Data AnalysisList metals in order by the amount of voltage they produce when used in a battery with 0.1 M HCl electrolyte solution (first voltage column). Start with the highest!


Table- metal, voltage, voltage, voltage

L6 text box[ The metals listed from highest voltage to lowest ] 27

List metals in order by the amount of voltage they produce when used in a lemon battery (second voltage column). Start with the highest!

Electrochemical BatteriesL6 text box[ The metals listed from highest voltage to lowest ]

28

List metals in order by the amount of voltage they produce when used in a tomato battery (third voltage column). Start with the highest!Electrochemical BatteriesL6 text box[ The metals listed from highest voltage to lowest ]

29AnalysisWhat components are necessary to make a battery?


L456 text box[ Batteries are made up of ] 30

AnalysisDid the type of electrochemical battery created (HCl, lemon, or tomato) affect the ranking of the metals? Electrochemical Batteries

L456 text box[ The type of electrochemical battery used ] 31

AnalysisWhat was the source of the electrons in the battery?

Electrochemical BatteriesL456 text box[ The electrons come from ] 32

AnalysisWhich pair of electrodes would make the most powerful battery? How do you know?Electrochemical Batteries

L456 text box[ The electrodes that will make up the most powerful battery are ] 33

SynthesisBatteries come in all shapes, sizes, and voltages. Car batteries, cell phone batteries, computer batteries, and flashlight batteries are all different from each other. Explain how each of these batteries are similar and suggest a reason for their different voltages.Electrochemical BatteriesL456 text box[ All of these batteries ] 34

SynthesisWhy do you think batteries go dead? Electrochemical Batteries

L456 text box[ Batteries go dead when ] 35

SynthesisWhy do you think many electronic devices require more than one battery?Electrochemical Batteries

L456 text box[ Electronic devices require more than one battery ] 36

Multiple ChoiceIn an electrochemical battery, electricity is generated by the flow of ___________. fruit metalsprotonselectrons


L6 text box[ The best choice is ]37

Multiple ChoiceIn a fruit battery, the fruit acts as ________. a metal electrons an electrolyte solution voltage



38

Multiple ChoiceVoltage is a measure of ______________.the number of electrons the difference between the desire for electronsthe time it takes for an electron to travel through a circuitthe concentration of salt in fruit

12 V batteryElectrochemical BatteriesL6 text box[ The best choice is ]39

Multiple ChoiceIn the fruit battery, the electrons were generated from _______________.the metal electrodethe fruitthe wirethe electrolyte solution



40Multiple ChoiceIn an electrochemical battery, chemical energy is converted to ___________. potential energy electricitysoundlight



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You have completed the lab.Congratulations!Please remember to follow your teacher's instructions for cleaning-up and submitting your lab.Electrochemical BatteriesColor scheme (RGB values)biology 121, 173, 54chemistry 0 176, 216physics 0, 102, 204earth 204, 102, 0middle 153, 102, 153elementary 255, 51, 0

42ReferencesElectrochemical BatteriesAll images were taken from PASCO documentation, public domain clip art, or Wikimedia Foundation Commons.

CARTOON CAR http://freeclipartnow.com/transportation/cars/car-ride.jpg.html LAMP http://freeclipartnow.com/household/furniture/desk-lamp.jpg.html OUTLET http://freeclipartnow.com/household/Electricaloutletandplug.jpg.html CELL PHONE http://freeclipartnow.com/electronics-technology/phones/mobile-phones/cellphone-crisp-small.jpg.html IPOD http://freeclipartnow.com/music/listening/ipod.jpg.html BOWLING BALL http://freeclipartnow.com/recreation/sports/bowling/blowling-ball-01.jpg.html BALANCED ROCK http://freeclipartnow.com/nature/scenery/Balanced-Rock-CO.jpg.html RUNNING MAN http://freeclipartnow.com/recreation/sports/fitness/running-man.jpg.html BATTERY http://freeclipartnow.com/science/energy/batteries/battery.jpg.html LIGHT BULB http://freeclipartnow.com/household/lightning/Lightbulb3.jpg.html CAUTION NO FOOD http://commons.wikimedia.org/wiki/File:D-P019_Essen_und_Trinken_verboten_ty.svg CAUTION FROM BATTERIES http://commons.wikimedia.org/wiki/File:D-W020_Warnung_vor_Gefahren_durch_Batterien_ty.svg KNIFE http://commons.wikimedia.org/wiki/File:Gemuesemesser.jpg SODIUM CHLORIDE http://commons.wikimedia.org/wiki/File:Sodium-chloride-3D-ionic.png LEMON http://freeclipartnow.com/food/fruits/lemons/lemon-simple.jpg.html TOMATO http://freeclipartnow.com/d/19948-2/tomato-casual.jpg BATTERY PILE http://commons.wikimedia.org/wiki/File:Versch._Batterien.JPG REMOTE http://freeclipartnow.com/recreation/entertainment/television-remote-control.jpg.html AA BATTERIES http://commons.wikimedia.org/wiki/File:Akku_AA_LR6_Mignon.jpg43

Voltage

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