SLHS Academic Chemistry Lab Notebook

Transcription

1 Name Teacher Six-Weeks SLHS Academic Chemistry Lab Notebook The most exciting phrase to hear in science, the one that heralds the most discoveries, is not "Eureka!" (I found it!), but that's funny..." Isaac Asimov

2 Table of Contents Page *Lab/Activity Flame Test Making the Connection ( other grade) Periodic Table Gallery Walk Create a Table Activity ( other grade) Periodic Trends Snowman Race Activity ( other grade) *Additional activities/manipulatives may be added at the end of the book or kept separate, per student s discretion. Lab quizzes may also be kept in the lab notebook. Would you like your own pair of goggles? Order from Flinn Scientific, Models AP3306 and AP3309 are both approved. Reminders: - Lost notebooks: students may print out additional copies of a lab from the website but 10 points will be deducted from the lab grade for each occurrence. - Late labs will be accepted with a 20 point deduction, per day late. - Goggles are to be worn at all times, unless instructed otherwise. 20 points will be deducted from the lab grade for the first goggle reminder and a grade of zero will be given for a second goggle reminder within the same lab period.

3 Name Flame Test Lab Per. Introduction: When metallic elements are heated to high temperatures, some of their electrons absorb energy and are therefore excited to higher energy levels. These excited electrons then fall back to the original lower energy levels, releasing the excess energy in packages of light called photons. The color of the emitted light depends on its energy. Different elements absorb and release different amounts of energy when heated; therefore, the color of the light emitted is characteristic for a particular element. The colors of light produced when substances containing metal ions are heated in a Bunsen burner are the basis of flame tests. Purpose: To determine how certain metal ions may be identified by the color they impart to a flame. Materials: Bunsen burners, sodium chloride, wooden splints soaked in solutions, tongs Procedure: 1. Wear safety goggles. 2. Lay a paper towel in the sink and dampen with water. Tie back hair and loose clothing. Light your Bunsen burner according to your teacher s directions. 3. Wet the tip of a dry wooden splint and put it in the dry salt. Burn the sample using tongs, and observe/record color emitted. Extinguish splint and place in sink on top of paper towel. 4. For the remainder of the samples (solutions), obtain a splint that has already been soaked in the solution. 5. Burn the sample using tongs and observe/record color; dispose of splint on paper towel. 6. Clean up by throwing away paper towel and all splints in the trash. Wash your hands. Data Table: Substance sodium chloride solid sodium chloride solution sodium nitrate solution copper (II) nitrate solution strontium nitrate solution Color observed in flame Substance calcium nitrate solution lithium nitrate solution potassium nitrate solution barium nitrate solution unknown Color observed in flame Questions: 1. What kind of element are flame tests used to identify? (read intro) 2. Which metal ion was present in your unknown? 3. Why do metal ions exhibit different colors in the flame? (read intro) 4. The energy of colored light colored light increases in the order red, orange, yellow, green, blue, violet. Arrange the following metallic ions used in the flame tests in order from lowest to highest energy: copper (II) nitrate, sodium nitrate, strontium nitrate (lowest) (highest) 5. Of the colors of visible light, which color has the highest frequency? Hint: energy is proportional to frequency (E = hν) 6. Which color has the longest wavelength? Hint: wavelength is proportional to frequency (c = λν)

4 Making the Connection Activity ORBITAL DIAGRAMS AND ELECTRON CONFIGURATIONS OF ELEMENTS 1 THROUGH 18 Ato mic # Element Symbol Orbital Diagram s 2s 2p 3s 3p Electron Configuration

5 Ato mic # ORBITAL DIAGRAMS AND ELECTRON CONFIGURATIONS OF ELEMENTS 19 THROUGH 36 Element Symbol Partial Orbital Diagram s 3d 4p Electron Configuration

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7 Making the Connection: Electron Configurations and the Periodic Table Useful information: Aufbau Order 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 6p 6 7s 2 5f 14 6d 10 7p 6 1. Note the numbers written on the lefthand margin of your periodic table. These are the period numbers. The first horizontal row (period) is Period 1, the second row is Period 2, and so on. 2. Refer to your completed worksheet Orbital Diagrams and Electron Configurations for Elements 1-18 to answer the following questions: 3. In the element boxes on your periodic table, write the notation for the last electron filled for elements 1 through 18. Example: the last electron filled for sodium goes in the 3s 1 spot, so I would write 3s 1 in the sodium box on the periodic table. When finished, answer these questions: Look at the first row of elements (H and He). What is the corresponding energy level for the s sublevel being filled here? Look at the second row of elements (lithium through neon). What is the corresponding energy level for the s and p sublevels being filled here? Look at the third row of elements (sodium through argon). What is the corresponding energy level for the s and p sublevels being filled here? How does the energy level for s and p electrons correspond to the period number? 4. What would you predict for the notation for the last electron in the configuration for calcium? Bromine? 5. Refer to your completed worksheet Orbital Diagrams and Electron Configurations for Elements to answer the following questions: 6. In the element boxes on your periodic table, write the notation for the last electron filled for elements 19 through 36. (Were you correct in your predictions in question 4?) When finished, answer these questions: Look at the fourth row of elements (potassium through krypton). What is the corresponding energy level for the s and p sublevels being filled here? 7. Looking at the pattern for s and p electrons in the Periodic Table, what would you expect for the notation for the last electron in the configuration for cesium? You should have predicted 6s 1. What about I? Did you predict 5p 5?

8 8. Using the pattern you have discovered, write the notation for the last electron filled for all of the representative elements in the boxes on your Periodic Table. (These are the Group A elements or elements in Groups 1-2, and ) 9. The transition metals are the Group B elements or elements in Groups Find Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn on your periodic table. What sublevel is being filled with these elements? What is the energy level of the sublevel being filled? What is the period # for these elements? 10. Determine the electron configuration for yttrium (#39) using the Aufbau order: What is the energy level of the last electron? What period is yttrium found in? 11. Using this pattern, fill in the rest of the d block for periods What would you predict for the notation for the last electron in the electron configuration for Pt? (Did you predict 5d 8?) 13. Let s look at the lanthanides. Shown below is the last electron filled for cerium (Ce) and lutetium (Lu). Write the notation on your periodic table for these two elements: Ce 4f 1 Lu 4f Using this pattern, fill in the notation for the last electron filled for the rest of the lanthanide series. Note: What sublevel is being filled with the lanthanides? What is the energy level of this sublevel? What period are the lanthanides in? 15. Let s look at the actinides next. Note the final electron being filled for thorium (Th) and lawrencium (Lr). Fill these in on your periodic table: Th 5f 1 Lr 5f Using this pattern, fill in the rest of the actinide series. What sublevel is being filled with the actinides? What is the energy level of this sublevel? What period are the actinides in? 17. Choose 4 different colored pencils. For every element, where the last electron being filled is in a/an: s sublevel color #1 p sublevel color #2 d sublevel color #3 f sublevel color #4 Make a legend on your periodic table telling which colors represent which blocks (Ex: s block = orange).

9 Name Per. Summary Questions for Making the Connection Fill in the blank: 5 points each (READ PREVIOUS PAGES FOR ANSWERS!) 1. The period # on the periodic table tells us the for the s and p sublevels. 2. Elements where the last electron is going into the s block are found in groups (#). 3. Elements where the last electron being filled is going into the p block are found in groups (#). 4. Elements in questions #2 & 3 are also known as the elements. 5. Elements where the last electron being filled is going into the d block are found in groups (#). 6. Elements in question 5 are also known as the metals. 7. Elements where the last electron being filled is going into the f block are found in the and series. Electron Configurations: 10 points each Now use your periodic table (not the Aufbau order) to write electron configurations for the following elements: WRITE #8-10 THE LONG WAY, AND USE THE SHORTCUT FOR # FULL CONFIGURATION: 8. nickel (#28) 9. strontium (#38) 10. cadmium (#48) SHORTCUT: 11. tin (#50) 12. xenon (#54) 13. lead (#82)

10 Insert Colored Periodic Table from Periodic Table Gallery Walk Here

11 NAME: GUIDED DISCOVERY OF THE PERIODIC TABLE I. History A. Mendeleev -known as? -organized elements by what kind of properties? -predicted? -organized periodic table in order of increasing? B. Moseley -worked with? Found relation between? -organized periodic table in order of increasing? C. Periodic Law (also known as the Law of Chemical Periodicity) -elemental properties are similar when? D. Seaborg -personal info -What did he do? What kind of prize did he win? E. Modern Periodic Table -periods arranged how? -group/family arranged how? II. Types of Elements A. METALS -location on periodic table 1.Alkali Metals -location, traits, uses, etc.

12 2. Alkaline Earth Metals -location, traits, uses, etc. 3. Transition metals -location, traits, uses, etc. 4. Inner-transition Metals: a. Lanthanide Series -location, traits, uses, etc. b. Actinide Series -location, traits, uses, etc. B. METALLOIDS -location, traits, uses, etc. C. NONMETALS -location, traits, uses, etc. 1. Halogens -location, traits, uses, etc. 2. Noble Gases -location, traits, uses, etc.

13 Summary of Physical and Chemical Properties: METALS versus NONMETALS PHYSICAL Properties: METALS NONMETALS CHEMICAL Properties: METALS NONMETALS

14 Name Per. Create-a-Table Activity Questions 1. What characteristics did you use for sorting the cards? 2. Where did you put H and He? What was your reasoning for their placements? 3. Did you notice any cards that didn t fit, or that seemed out of order? Explain. 4. Below are 5 possible cards for the element germanium. Which seems most accurate, based on the table you created? Explain your reasoning. 5. What would you add to the three empty corners to complete this card? 6. Which of the following elements would not be found in the same group with the others? Explain your thinking.

15 7. What trend do you notice for the size (radius) of the atoms across a period (left to right)? Down a group? 8. Note that for metals, down a group, the color intensity increases. What does that represent? 9. How is state of matter (solid, liquid, or gas) symbolized on the atom models? 10. What detail on the atom models is different for metals compared to metalloids and nonmetals? 11. What do the pegs on the atom models symbolize?

16 Element Lab Activity: Periodic Trends Electronegativity Straw Length (cm) Ionization Energy Straw Length (cm) Atomic Radius Straw Length (cm) 1 H He n/a Li Be B C N O F Ne n/a Na Mg Al Si P S Cl Ar n/a K Ca Ga Ge As Se Br Kr n/a Rb Sr In Sn Sb Te I Xe n/a

17 Lab Activity: Periodic Trends Introduction: In this activity, you will model three properties of the elements that show trends across a period and down a group on the periodic table. These properties are: Atomic Radius: a measure of the size of one atom of an element Ionization Energy: the measure of the energy required to remove an electron from the outermost energy level of an atom Electronegativity: the tendency of an atom to attract electrons to itself when it is chemically bonded with another element Straws cut to specific lengths will be used to represent the values of these properties for selected elements (see chart on last page). Straws will be placed vertically in well plates, with each well corresponding to a chemical element. Once the model is assembled, the student will have a visual representation of the trends in the properties, across the periods and down the groups of the periodic table. Procedure: 1. Obtain supplies: 1) a bag of straws labeled with one of the above properties; 2) a well plate with periodic table attached to the back; 3) a ruler. 2. Take out your straws and lay them in order of length on the lab table. 3. Using the chart on the last page and a ruler, find the straw that has been cut to the appropriate length for hydrogen. Make sure you are looking at the column that matches the property on your baggie! 4. Place the straw in the well that corresponds to hydrogen. 5. Repeat steps 2-3 for the rest of the elements in the chart. 6. Keeping your model assembled, answer the questions on the back of this page for your trend. 7. Rotate to another lab station and view the completed model for the second property. Answer the questions on the back for that trend. 8. Rotate to a third lab station and view the completed model for the third property. Answer the questions on the back for that trend.

18 Name Per. Questions on Periodic Trends Trend 1: Atomic Radius 1. From top to bottom down a group, this trend (circle one) increases / decreases. 2. WHY do we observe this group trend? SEE CLASS NOTES 3. Which element has the larger atomic radius, (circle one): beryllium or radium 4. From left to right across a period, this trend (circle one) increases / decreases. 5. WHY do we observe this periodic trend? SEE CLASS NOTES 6. Which element has the larger atomic radius, (circle one): cesium or astatine? Trend 2: Ionization Energy 7. From top to bottom down a group, this trend (circle one) increases / decreases. 8. WHY do we observe this group trend? SEE CLASS NOTES 9. Which element has the greater ionization energy, (circle one): lithium or francium? 10. From left to right across a period, this trend (circle one) increases / decreases. 11. WHY do we observe this periodic trend? SEE CLASS NOTES 12. Which element has the greater ionization energy, (circle one): strontium or iodine? Trend 3: Electronegativity 13. From top to bottom down a group, this trend (circle one) increases / decreases. 14.WHY do we observe this group trend? SEE CLASS NOTES 15. Which element has the greater electronegativity, (circle one): carbon or lead? 16. From left to right across a period, this trend (circle one) increases / decreases. 17. WHY do we observe this periodic trend? SEE CLASS NOTES 18. Which element has the greater electronegativity, (circle one): potassium or bromine?

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