Aren't Acids and Bases pHabulous?


Hello, Chemists!

We will be exploring different systems of measurement in this next unit. Remember the metric scale? Oh yeah, we are going to learn an even cooler scale - in fact, its pHabulous! The pH scale measures the amount of hydrogen ions in a specific chemical. Lemonade has a pH value, Battery fluid has a pH value, even water has a pH value! 

Over the next week we will be learning the pH scale, examples of different values, and how to test a value. We will then be putting our knowledge on its feet with an experiment next week!

But first, we must work on our pH knowledge mastery! Complete each task by reading the material, watching the video, and answer the mini-quiz questions. 

Good luck! 


Task 1 

Start by watching this video to learn more about the history of the pH scale and why we use it still today!


Task 2 

Read the following article to learn examples of different values on the pH scale.


Task 3 

After reading the article, take this short quiz to see what you know!

  1. A hydrogen ion, H+, is the same as a(n):

    • neutron
    • electron
    • proton
    • hydroxide ion
  2. Acidic foods can be identified by what taste?

    • salty
    • sour
    • bitter
    • sweet
  3. OH- is called the:

    • hydrate ion
    • hydrogen ion
    • hydronium ion
    • hydroxide ion
  4. Acids increase the concentration of what in water?

    • H+ ions
    • hydrate ions
    • hydroxide ions
    • OH- ions
  5. Bases can be referred to as:

    • none of the choices
    • proton acceptors
    • proton donors
    • protons
  6. A beaker full of acid is added to a beaker full of base. The pH of the base will:

    • change constantly
    • decrease
    • increase
    • stay the same
  7. What is the concentration of H+ in pure water?

    • 1 x 10-13 moles/liter
    • 1 x 10-14 moles/liter
    • 1 x 10-7 moles/liter
    • 1 x 107 moles/liter
  8. A solution with a pH of 11 has a H+ concentration of:

    • 1 x 10-11 moles/liter
    • 1 x 10-3 moles/liter
    • 1 x 1011 moles/liter
    • 1 x 103 moles/liter
  9. Which substance has the lowest pH?

    • milk
    • NaOH
    • pure water
    • lemon juice
  10. An unknown substance is added to a solution and the pH increases. The substance is:

    • acidic
    • basic
    • solvent
    • sweet

Task 4 

Based on your quiz answers, head on over to this website for an interactive game to practice your pH knowledge!!/media/1390445/ph-acids-and-bases




You’ve completed all the assignment. For your final assignment you be presenting you will working in pairs to determine the pH levels of certain liquids in class on experiment day! 


Image result for ph scale

Teacher Page

The webquest is designed to for preparation for an experiment in the classroom. The material is alligned with NGSS Standard: 

MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred. 

Students will build upon their understanding of scientific measurement scales and how chemical properties can change. Students will build their knowledge of the chemical makeup of specific liquids and how the polarity of water plays a neutralizing part in reactions. This site is intended to be a class activity and an at-home activity for students who want extra practice and information in regard to acidity.