Lesson 2.4: Investigation: Acids and Bases, Pages 1 and 2

You will now apply your knowledge of acids and bases to use various tests to identify substances as acids or bases.  This investigation is a computer investigation. 

  1. Insert the science.connect 1 Student Multimedia CD into your computer. 
  2. Launch the applet "Acids and Bases", and complete the first two pages:
  3. Do not close the applet until you have finished the entire investigation because you will likely have to flip back and forth between the applet and this course. 
  4. Now, answer the following questions.  

Question 1. Where are acids and bases used?

Question 2. Page 2 "The pH Continuum" has a sliding pH scale that gives the names of some common substances. 
a) Move the orange slider to pH = 13.0.  What is the name of the substance that has a pH = 13.0 on the scale? 
b) Move the orange slider to pH = 1.0.  What is the name of the substance that has a pH = 1.0 on the scale?

Question 3. Mouse-over the "Did You Know" button on page 2 to learn what a pH unit means in terms of relative acidity or basicity. 
a) How many times more acidic is a solution with a pH of 3 compared to a solution with a pH of 5? 
b) How many times more basic is a solution with a pH of 13 compared to a solution with a pH of 10?

 

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. Where are acids and bases used?

Acids and bases are used in the home, in the lab, and in the workplace.

Question 2. Page 2 "The pH Continuum" has a sliding pH scale that gives the names of some common substances. 
a) Move the orange slider to pH = 13.0.  What is the name of the substance that has a pH = 13.0 on the scale? 
b) Move the orange slider to pH = 1.0.  What is the name of the substance that has a pH = 1.0 on the scale?

a)The substance that has a pH = 13.0 on the scale is lye. 
b)The substance that has a pH = 1.0 on the scale is stomach acid.

Question 3. Mouse-over the "Did You Know" button on page 2 to learn what a pH unit means in terms of relative acidity or basicity. 
a) How many times more acidic is a solution with a pH of 3 compared to a solution with a pH of 5? 
b) How many times more basic is a solution with a pH of 13 compared to a solution with a pH of 10?

The information stated that each pH unit represents a tenfold change in acidity or basicity. 
a) The solution with a pH of 3 is 100 times as acidic as a solution with a pH of 5. 
b) A solution with a pH of 13 is 1000 times as basic as a solution with a pH of 10.

 


Click on the page forward to continue this investigation of Lesson 2.