The Physical Sciences Initiative Chemistry Inservice D A T A O G G I N G The Electrochemical Series for Graphic Calculator & Computer Nov 2001 1
The Electrochemical Series. This experiment will allow the student to arrange a selection of five metals in order of reactivity. The metals are placed on solutions of their salts and mini voltaic cells are created by connecting pairs of metals using the Voltage Sensor and noting the direction of the flow of electrons. The aim is to get a positive reading on the calculator. The Red lead is the Cathode and the Black lead is the Anode. When a positive reading is produced, the metal connected to the black lead is the more reactive of the two and is higher in the electrochemical series. If a negative reading is obtained just reverse the leads. Students should record the results in the table provided and from these results place the metals in order of reactivity. Apparatus 1. CB 2 datalogger with DataMate Program 2. TI-83 Graphing Calculator 3. Voltage Sensor. 4. Filter paper and scissors. 5. Sand paper and forceps 6. 1 M solns. of,,zn,mg and 7. Small clean pieces of,,zn,mg and 8. 1 M NaNo3 used as a salt bridge NaNO 3 soln. used as a salt bridge t out sections between metals 2
Setting up the calculator and datalogger Place the Calculator in the cradle. Place the CB 2 datalogger on the underside of the cradle. Place the Voltage Sensor in channel 1 of the CB 2. Connect the Calculator to the CB 2 using the small connection lead. Make sure the lead is pressed fully home. (The connection ports are at the bottom of the Calculator and CB 2). If the sensor is connected before the Calculator is turned on, it will be automatically detected. Selecting the Sensor The Sensor Menu More sensor Menu Turn on the Calculator. Press APPS (blue key). From the menu that appears select the Datamate program by pressing the appropriate number. Press CEAR ( Removes any data present from previous experiments) Channel 1 should show the Voltage Sensor is attached. If the Voltage Sensor is not detected in channel 1, then it must be selected from the sensor menu. Press 1 Setup Press ENTER at channel 1 3
Choose More until the voltage sensor appears Choose 1 for the Voltage Sensor. Procedure for the Experiment and collecting the Data Students should wear safety goggles and surgical gloves when handling the chemicals as some are poisonous and some cause hard-to-remove stains. t wedges in the filter paper as in the diagram. Place a few drops of SO4 on one section and place a piece of Copper metal on the wet spot Try to ensure that the upper surface of the metal is dry. Repeat this for each of the other metals and their solutions. Add the NaNO3 solution to the filter paper along the lines as shown in the diagram. Push the ends of each lead of the Voltage sensor to expose the contact points. Touch the red lead to one metal and the black lead to another and note the positive voltage displayed on the calculator. If the voltage is negative, reverse the leads. Record in the table provided the size of the voltage, which metal was in contact with the black (more reactive) and which one was in contact with the red (less reactive of the pair.) Identify the metal that is the higher of the two. Complete the table for all the pairs of metals in the table. When the table is complete dispose of the apparatus as directed by your instructor. Results 4
TABE 1 Voltaic cell (metals used) Mg / Potential or Voltage reading of (+) lead RED of ( ) lead BACK Order of the pairs of metals ow Mg / ow Mg / ow Mg / Zn ow / ow / ow / Zn ow / ow / Zn ow / Zn ow From the results above place the metals in order of reactivity TABE 2 Order of metals in Electrochemical series est owest 5
TABE 1 SPECIMEN RESUTS Voltaic cell (metals used) Mg / Mg / Mg / Mg / Zn / / / Zn / / Zn / Zn of (+) lead RED of ( ) lead BACK Mg H Mg Order of the pairs of metals Mg H Mg Mg H Mg Zn Mg H Mg Zn H H Zn H Zn H Zn H Zn Zn H Zn TABE 2 SPECIMEN RESUTS Order of metals in Electrochemical series est owest Mg Zn 6
The Electrochemical Series This experiment will allow the student to arrange a selection of five metals in order of reactivity. The metals are placed on solutions of their salts and mini voltaic cells are created by connecting pairs of metals using the Voltage Sensor and noting the direction of the flow of electrons. The aim is to get a positive reading on the calculator. The Red lead is the Cathode and the Black lead is the Anode. When a positive reading is produced, the metal connected to the black lead is the more reactive of the two and is higher in the electrochemical series. If a negative reading is obtained just reverse the leads. Students should record the results in the table provided and from these results place the metals in order of reactivity. Apparatus and Chemicals 1. abpro data logger. 2. PC with ogger Pro software installed 3. USB port connecting cable 4. Voltage Sensor. 5. Filter paper and scissors. 6. Sand paper and forceps 7. 1 M solns. of,,zn,mg and 8. Small clean pieces of,,zn,mg and 9. 1 M NaNo3 used as a salt bridge Setting up the Data logger and PC THE DATAOGGER Connect abpro to the computer via the USB cable.you may need to slide the plastic window on the side of the data logger to access the port. Connect the Voltage Sensor to channel 1 on the abpro Attach the power lead to abpro and turn it on. 7
THE COMPUTER Double click on the ogger Pro icon on the desktop. If there is no icon displayed the program is found by clicking Start followed by Programs, followed by Vernier Software and finally ogger Pro. If the program does not detect the Sensors. Follow these instructions. Click on File, select Open. Double Click on Chemistry with Computers. Double Click on Exp. 28 Micro Voltaic Cells. Click on Exp. 28 abpro.voltage. Click on Setup on the top Toolbar and select Sensors. Click on Channel 1.From the drop down Menu select Voltage(-10V to +10V) Click on O.K The screen is divided into two main areas. Meter Window this shows the reading recorded by the current sensors. Table Window Entries are recorded here in columns.(similar to Spreadsheet) Click on X in the Table Window as it is not needed. You are now ready to record data 8
. Procedure for the Experiment and collecting the Data Students should wear safety goggles and surgical gloves when handling the chemicals as some are poisonous and some cause hard-to-remove stains. NaNO 3 soln. used as a salt bridge t out sections between metals t wedges in the filter paper as in the diagram. Place a few drops of SO4 on one section and place a piece of Copper metal on the wet spot. Try to ensure that the upper surface of the metal is dry. Repeat this for each of the other metals and their solutions. Add the NaNO3 solution to the filter paper along the lines as shown in the diagram Push the ends of the leads to expose the contact points. Touch the red lead to one metal and the black lead to another and note the positive voltage displayed on the Meter Window. If the voltage is negative, reverse the leads The readings are recorded in the table provided in this handout. Which metal was in contact with the black (more reactive) and which one was in contact with the red (less reactive of the pair.) is also recorded. Identify the metal that is the higher of the two. Complete the table for all the pairs of metals in the table. From the results place the metals in order of reactivity When the table is complete dispose of the apparatus as directed by your instructor. 9
Results TABE 1 Voltaic cell (metals used) Mg / Potential or Voltage reading of (+) lead RED of ( ) lead BACK Order of the pairs of metals ow Mg / ow Mg / ow Mg / Zn ow / ow / ow / Zn ow / ow / Zn ow / Zn ow From the results above place the metals in order of reactivity TABE 2 Order of metals in Electrochemical series est owest 10
TABE 1 SPECIMEN RESUTS Voltaic cell (metals used) Mg / Mg / Mg / Mg / Zn / / / Zn / / Zn / Zn of (+) lead RED of ( ) lead BACK Mg H Mg Order of the pairs of metals Mg H Mg Mg H Mg Zn Mg H Mg Zn H H Zn H Zn H Zn H Zn Zn H Zn TABE 2 SPECIMEN RESUTS Order of metals in Electrochemical series est owest Mg Zn 11