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L5.3

Where do all of the elements from your smartphone come from?

QUESTION: Where do all of the elements in our smartphone come from?

Learning Objectives:

  • Connect the abundance of elements in the Earth’s crust to the origin of the elements.  
  • Explore the origin of the elements by modeling nuclear reactions, specifically nuclear fusion. 
  • Recognize the fusion reactions that take place in the sun. 

Warm-up:

  • Attendance 
  • Open Student IMT Unit 5, make sure all lessons are complete.   

IN-CLASS WORK:

  • Open (H) L5.3 Student Sheet , make a copy and add to your google drive
    • Part 1: Abundance of elements
    • Part 2: Critical Thinking Questions
    • Part 3: How are elements formed? 

OUT-OF-CLASS WORK:

  • Open IMT for Unit 5 and make sure all sections for lesson 3 are complete. 
  • Make sure student sheet L5.3 is complete and complete the check for understanding on Schoology.

L5.3 Student Sheet

Lesson 5.3: Where do all the elements in our smartphones come from?

Exploring the Smartphone Elements with Periodic Tables of Elements (PTE) 

Part 1:  Complete Table - detailed instructions below (pg 2)

Part 2:  Answer Critical Thinking Questions

Element Name
Location		 Element Symbol Atomic Number Average Atomic Mass Most abundant isotope name protons electrons neutrons isotope symbol
(mass number & atomic number)		 FROM PTE of Abundance Element in Earth’s Crust (mg/kg)
Aluminum
Battery		 Al 13 26.982 amu Aluminum - 27 13 13 14 13 - 27 Al 82300
Gold
Electronics		 Au 79 197 amu Gold - 197 79 79 118 79 - 197 Au 0.0002
Copper
Electronics		 Cu 29 63.546 amu Copper - 63 29 29 34 29 - 63 Cu 55
Lithium
Battery		 Li 3 6.939 amu Lithium - 7 3 3 4 3 - 7 Li 20
Silicon
Electronics		 Si 14 28.086 amu Silicon - 28 14 14 14 14 - 28 Si 2770
Phosphorous
Electronics		 P 15 30.97 amu Phosphorus - 31 15 15 16 15 - 31 P 2
Dysprosium
Screen		 Dy 66 162.5 amu Dysprosium -163 66 66 97 66 - 163 Dy 0.00005
Tungsten
Electronics		 W 74 183.8 amu Tungsten - 184 74 74 110 74 - 184 W 0.0001
Praseodymium
Screen		 Pr 59 140.9 amu Praseodymium -141 59 59 82 59 - 141 Pr 0.00001

Part 1 - Complete the table using these directions

  1. Aluminum is completed for you in the table as an example.

  2. For Columns A-C, use the regular periodic table of elements (PTE) (found here) to determine the element symbol, the atomic number, and the average atomic mass.

  3. For Column D, use the internet to find the most abundant isotope for this element, write this in the table using the isotope name format of element name - mass number. For example write:  Aluminum - 27 (Aluminum is the element name - 27 is mass number of this isotope of aluminum.)

  4. For Columns E-F, use the PTE (found here) to determine the protons and electrons for each element.

  5. For Column G, determine the number of neutrons by taking the most abundant isotope mass number and subtracting the number of protons from it.  For example, the most abundant isotope of Aluminum is 27.  Aluminum always has 13 protons.  To obtain the number of neutrons, use the equation (mass number - # protons = # neutrons).  For Aluminum-27:  27-13 = 14.  There are 14 neutrons in this isotope of aluminum. 

  6. For Column H, write the isotope symbol by placing the mass number on top to the left of the symbol and the atomic number on bottom to the left of the symbol.  See the example of Aluminum in the chart. 

  7. For Column I, use the “Abundance of Elements in the Earth’s Crust” PTE (found here) to find the abundance value for each element.  The units for these numbers are (mg/kg).  

Part 2 - Using your completed chart answer the following questions

  1. Why does the atomic number change from element to element?

The atomic number of an element is determined by the number of protons in the nucleus of an atom. As the number of protons in the nucleus changes, so does the atomic number. Elements are arranged on the periodic table in order of increasing atomic number.

  1. If two elements are next to each other such as Hydrogen and Helium, how do their atomic numbers compare?  What does that tell you about the number of protons? 

The atomic number of Hydrogen is 1 and the atomic number of Helium is 2. This tells us that Helium has one more proton in its nucleus than Hydrogen.

  1. How could you change Silicon (14) to Phosphorus (15)? 

Silicon can be changed to Phosphorus by either adding or removing a proton from the nucleus. This can be achieved through a process called nuclear transmutation, which involves bombarding the nucleus of an atom with a high-energy particle, such as a neutron, proton, or alpha particle.

  1. Do you think that in a high school chemistry class we could change silicon to phosphorus?  Why or why not?

It is unlikely that a high school chemistry class would have the equipment or resources to change silicon to phosphorus through nuclear transmutation. This process typically requires a high-energy particle accelerator and specialized equipment.

  1. Which three elements are the most abundant in the Earth’s Crust from this chart? List the element and the atomic number starting with most abundant.

MOST ABUNDANT: 2nd MOST ABUNDANT: 3rd MOST ABUNDANT:

  1. Which three elements are the least abundant in the Earth’s Crust from this chart? List the element and the atomic number ending with least abundant.

  2. What do you think might be a general correlation between atomic number and abundance in the Earth’s Crust?

  3. Look at the periodic table here, find iron, Fe. 

  4. What is the atomic number? _________

  5. What is the abundance______________

  6. Using iron, Fe, as the center point, let’s divide the periodic table into two major groups.  

Group 1:  Elements with atomic numbers lower than Fe (atomic number 1 - 25).

Group 2:  Elements with atomic numbers higher than Fe (atomic numbers 27 - 92).  

How does the overall abundance in the Earth’s Crust of Group 1 compare to Group 2?

  1. All elements on the periodic table starting with helium, He, and increasing in atomic number to iron, Fe, are created from nuclear fusion reactions. What do you think a nuclear fusion reaction is? 

Part 3 - How are Elements formed? 

  1. (Watch video)

  2. Write 2-3 things that surprised you after watching this video.

  3. Write 1 thing that you learned.

  4. (Watch simulation)

  5. Does this simulation portray fusion or fission?  Explain your answer using evidence.

  6. Where does the energy come from during this process of a bomb detonating?

  7. Is the mass of each nucleus heavier or lighter after detonation or when energy was released?  Explain your answer using evidence.

  8. On the simulation, use the slider to determine a certain number of uranium nuclei (Pick a number greater than 50 nuclei).   When each nucleus split, it gives off 2×108 eV of energy.  Calculate the amount of energy given off when your bomb was detonated.  Show work below. 

  9. If 1 eV = 1.60218 x 10-19 J, then how many kJ of energy was produced from the detonation of your bomb?

  10. If the atomic bomb that exploded in Hiroshima released 63 TJ of energy (1 TJ = 1x 1012J), then what was the minimum mass of the uranium used assuming all nuclei split and give off energy?  (Hint: use E = mc2)

  11. How many nuclei underwent fission?  (Hint: 1 nucleus of uranium has a mass of 3.95 x 10-22 g). 

  12. An explosion of an atomic bomb releases 7.6×1013 J energy.  If 200 MeV (M = mega → 1 x 106) energy is released on the fission of one 235U atom, then what is the number of uranium atoms undergoing fission? (Hint - 1 eV = 1.60218 x 10-19 J)

NEXT STEPS:

  1. Reflect on today’s question: How abundant are the elements in the smartphone? 

  2. Open up the IMT for this unit, complete all boxes for lesson 3.

  3. Make sure all parts of the L5.3 student sheet are complete and then complete the check for understanding on Schoology.

Last update: June 5, 2023
Created: June 5, 2023