*What should we do at the end of the life of a smartphone? Reuse? Recycle? Dispose of?

Part 1: Revisiting Conservation of Mass (Show ALL calculations)¶

We began with about 0.10 g of copper which is 1.57 x 10-3 moles of copper.¶

How many atoms of copper are in this sample? Show all calculations.¶

$\(1.57 * 10^{-3} * 6.02 * 10^{23} = 9.4514 * 10^{20}$\)

What is the mass of copper we should have at the end of this cycle assuming excellent technique?¶

\[0.1g$$ ### How many moles of copper atoms should we have at the end of this cycle assuming excellent technique? $$1.57 * 10^{-3}$$ ### How many atoms of copper atoms should we have at the end of this cycle assuming excellent technique? $$9.4514 * 10^{20}\]

STEP 1: Cu(s) + 4 HNO3(aq) → Cu(NO3)2 (aq) + 2 NO2 (g) + 2 H2O (l)¶

Look at the balanced equation, what is the ratio of Cu (s) : Cu(NO3)2 (aq)?¶

\[1:1\]

What is the molar mass of copper (II) nitrate?¶

\[Cu(63.546) + 2N(14.007) + 6O(15.999) = 187.56\frac{g}{mol}\]

At the end of STEP 1, there are 1.57 x 10-3 moles of copper (II) nitrate formed as indicated by the ratio in the balanced equation. What is the mass of this amount of copper (II) nitrate?¶

\[Cu(NO_{3})_{2}\left( 187.56 \frac{g}{mol}\right) * 1.57 * 10^{-3} = 2.944692 * 10^{-1}\]

STEP 2: 2 NaOH (aq) + Cu(NO3)2 (aq) → Cu(OH)2 (aq) + 2 NaNO3 (aq)¶

Look at the balanced equation, what is the ratio of Cu(NO3)2 (aq) : Cu(OH)2 (aq)?¶

\[1:1\]

What is the molar mass of copper (II) hydroxide?¶

\[Cu(63.546AMU) + 2O(15.999AMU) + 2H(1.008) = 97.561 \frac{g}{mol}\]

At the end of STEP 2, there are 1.57 x 10-3 moles of copper (II) hydroxide formed as indicated by the ratio in the balanced equation. What is the mass of this amount of copper (II) hydroxide?¶

$$$$

STEP 3: Cu(OH)2 (aq) + Heat → CuO (s) + H2O (l)¶

Look at the balanced equation, what is the ratio of Cu(OH)2 (aq) : CuO (s)? __________¶

What is the molar mass of copper (II) oxide?¶

At the end of STEP 3, there are 1.57 x 10-3 moles of copper (II) oxide formed as indicated by the ratio in the balanced equation. What is the mass of this amount of copper (II) oxide?
STEP 4: CuO (s) + H2SO4 (aq) → CuSO4 (aq) + H2O (l)
Look at the balanced equation, what is the ratio of CuO (s) : CuSO4 (aq)? __________
What is the molar mass of copper (II) sulfate?
At the end of STEP 4, there are 1.57 x 10-3 moles of copper (II) sulfate formed as indicated by the ratio in the balanced equation. What is the mass of this amount of copper (II) sulfate?
STEP 5: CuSO4 (aq) + Zn (s) → ZnSO4 (aq) + Cu (s)
Look at the balanced equation, what is the ratio of CuSO4 (aq): Cu (s)? __________
What is the molar mass of copper?
At the end of STEP 5, there are 1.57 x 10-3 moles of copper formed as indicated by the ratio in the balanced equation. What is the mass of this amount of copper?
What do you think is the role of the ratio between two chemicals in an equation?
How did this experiment and the calculations support the law of conservation of mass?

Part 2: Cost of copper calculations

Review the article, ‘Your old phone is full of untapped precious metals’.

If the current price of copper is $0.010248 per gram and there are 12 grams of copper in a smartphone, what is the cost of copper in your smartphone? Show your calculation
According to this article, one million smartphones could deliver how much copper in tons? _________
Where, according to this article, is the largest e-waste site in the world? ____________

Part 3: Environmental impacts of copper mining as reported by the OECD

Refer to the diagram of material flow and the table of recycling rates from the OECD report to answer the following. The complete report, ‘Reducing the Health Risk of Copper, Rare Earth, and Cobalt Industries’, is provided here for additional information, if interested.

What does OECD abbreviation represent? ______________________________
How many countries are in the OECD? _________________________________
What is the year of this report? ________________
Why is this a good source of information? ______________________________
From the table of recycling rate and the diagram of material flow, answer the following questions.
What is the recycling rate for copper, Cu metal? _______________________
What is the recycling rate for lithium, Li metal? _____________________
State two advantages of recycling waste.

Part 4: Write a revised CER -

Complete the Unit 4 IMT, making sure that you have the information you need for this to be a study guide for the assessment next class.
Using the information that we learned in this unit and your updated IMT for Unit 4, write a revised CER in paragraph form that answers the unit question: At the end of your smartphone life, will you recycle, reuse, or dispose of your smartphone? Be sure to include chemistry. Use the CER graphic organizer if helpful.

Your revised CER Paragraph:**

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