The pH Detectives! 🧪

Introduction

🔍 Mission: Catch the Criminal Who Changed the Water!    ❌ Photo unavailable

🧠 Hook (Engage)

🚨 Emergency Alert!

Something strange happened in the school water tank! The water is no longer safe… scientists suspect that different substances entered the tank and changed its properties.

👩‍🔬👨‍🔬 Your mission: Become a pH Detective and identify the criminal using science evidence!

Task

❌ Photo unavailable

🎯 Task:

By the end, you will be able to:

  1. 🟢 Define the pH scale and its range (0–14) 
  2. 🔵 Explain acids, bases, and neutral substances 
  3. 🟡 Classify substances using pH values 
  4. 🟠 Analyze the pH scale (strong vs weak) 
  5. 🔴 Evaluate safety using pH values 

Process

❌ Photo unavailable

🔍 PROCESS: THE INVESTIGATION

🟢 STEP 1: Observe the Crime Scene 

🎥 Watch:

 

 

 

https://youtu.be/EhUpsq2i6k0

 

🕵️ The water tank has been contaminated!

✏️ Answer the questions below on your sheets "PH Detective Case report ":

  1. What happened to the water in the tank?
  1. List the suspects found near the water tank:
  •  
  •  
  •  
  1. Classify each suspect:
Substance Acid / Base / Neutral
Lemon juice  
Milk  
Baking soda  
  1. Which suspect do you think caused the change? Why?

🔵 STEP 2: Reveal the Truth 

🎥 Watch:

 

https://youtu.be/WrPEosrV_c4

 

 

 

 🧪 Scientists used the pH scale to investigate!

✏️ Answer the questions below on your sheets "PH Detective Case report ":

  1. What is the pH scale?
  1. Complete:
  • Lemon → __________ color
  • Baking soda → __________ color
  • Milk → __________ color
  1. Final suspect based on evidence:
  • Criminal: __________
  • Type: ☐ Acid ☐ Base ☐ Neutral
  • Evidence: _________________________________________________________________________________________

🟡 STEP 3: Scientific Testing (Apply)

🧪 Use PhET Simulation:

https://phet.colorado.edu/en/simulation/ph-scale

✏️ Record your findings:

Substances pH Value Type
Orange juice    
Milk    
Drain cleaner    

✏️ Answer:

  1. Which substance is most acidic?
  2. Which is most basic?
  3. What happens to color as pH changes?

 

 

🟣 STEP 4: FINAL REPORT ( Padlet Mission)

🎨 You are now a Certified pH Detective!

📌 Padlet Post Instructions

Create your Padlet post carefully and make sure it looks like a real investigation report 🕵️‍♂️🧪

https://padlet.com/abedalrahmanalrai/ph-scale-r0hr1uzs740rt7sn

 

✔️ Your Padlet post must include:

 

1. Title🧾 Write:

“PH Detective Case Report – [Your Name]”

2. Evidence Upload

📸 Upload screenshots clear of:

  • Your answers from Step 1, Step 2, and Step 3

3. pH Scale

📊 Include ONE of the following:

  • A hand-drawn pH scale, OR
  • An inserted image of the pH scale

4. Final Scientific Answers (Full Sentences ✏️)

✏️ Answer clearly:

  1. Is a liquid with pH 2 safe to drink? Why?
  1. Which is more dangerous: pH 1 or pH 13? Explain.

🧠 Detective Reminder

  • Use scientific words (acid, base, neutral, pH)
  • Write in full sentences
  • Support your answers with evidence from your investigation

Evaluation

🎯 I can show my learning in this WebQuest!

Criteria 🌟 Excellent Scientist (4) 👍 Good Work (3) 🌱 On the Right Track (2) 🧩 Keep Trying (1)
🟢 pH Scale (0–14) I can clearly define the pH scale and explain its full range (0–14) confidently. I can explain the pH scale with small mistakes. I understand some parts of the pH scale but not fully. I am still confused about the pH scale.
🔵 Acids, Bases & Neutral I can explain acids, bases, and neutral substances with correct examples. I can explain most of them with minor errors. I understand some of the concepts but not all. I find these concepts difficult to understand.
🟡 Classifying substances (pH values) I can correctly classify all substances using pH values and reasoning. I can classify most substances correctly. I can classify some substances but need help. I am not yet able to classify substances correctly.
🟠 PhET Simulation (strong vs weak) I can analyze strong and weak acids/bases using pH values clearly. I understand strong and weak substances with small mistakes. I have a basic idea but need more practice. I am still struggling to understand the simulation.
🔴 Safety & real-life thinking (Padlet) I can explain how pH affects safety in real life clearly and confidently. I can explain safety with some ideas. I give simple ideas about safety. I need help understanding safety connections.
🎨 Final Padlet Presentation My Padlet is complete, clear, creative, and well organized. My Padlet is mostly complete with minor missing parts. My Padlet is incomplete or unclear in some parts. My Padlet is incomplete or missing important parts.

 

🏁 TOTAL SCORE: ____ / 24

🌟 MY SCIENTIST MESSAGE

I am learning to think like a scientist 🧪

I am improving my observation and reasoning skills 🔍

I am becoming a confident pH Detective 🌈

Conclusion

Conclusion

🎉 CONCLUSION ❌ Photo unavailable

🕵️‍♀️ Great work, pH Detectives!

You investigated a mystery using the pH scale, classified substances as acids, bases, or neutral, and used scientific evidence to identify the cause of the water change.

🔬 The pH scale is an important tool, but it is not the only way scientists study substances. We also have other methods that we will learn about, such as indicators, which help us detect acids and bases. Scientists can use different natural and artificial indicators such as red cabbage juice, litmus paper, and other solutions to observe color changes and identify substances.

🌟 Next time, we will explore and test other indicators to compare how they help us identify acids, bases, and neutral substances more clearly.

Credits

📌 CREDITS & RESOURCES

🧪 This WebQuest was designed for Grade 6 Science learning to explore the pH scale, acids, bases, neutral substances, and indicators through inquiry-based learning.

🎥 VIDEOS USED

🧪 INTERACTIVE SIMULATION

📌 LEARNING PLATFORM

Credits

📌 CREDITS & RESOURCES

🧪 This WebQuest was designed for Grade 6 Science learning to explore the pH scale, acids, bases, neutral substances, and indicators through inquiry-based learning.

🎥 VIDEOS USED

🧪 INTERACTIVE SIMULATION

📌 LEARNING PLATFORM