Name ___________________
1
Period __________
Go to: phet.colorado.edu  “Play with simulations”  pH scale  Click play button
1. Click on MACRO. Take a few moments to play around with the simulation to see what the various buttons are.
2. Look at the scale to the left.
A. What does it measure? _________________________
B. Which numbers represent an acidic solution? __________________
C. Which numbers represent a basic solution? __________________
3. From the drop-down menu, look at the list of solutions. List them from the lowest pH to the highest pH. List the pH
and indicate if the solution is acid, basic, or neutral.
Solution
pH
Acidic/basic/neutral
4. Go back to the home page, and click on MICRO. What is the meaning of pH?
A. What are the three quantities measured by the scale on the left?
_______________________________________________
B. Toggle the top scale to concentration.
1. What are the units of concentration? ________________
2. Remember from the last chapter. What is another name for these units? ____________
C. The switch below the scale should read logarithmic. What is the range of values for concentration?
________________
a) Change these values to standard notation (without the exponent)
2. Which is the largest number on the scale (as an exponent)?_____________ The smallest? ____________
D. Change the solutions and look at the concentration values. Which concentration level always stays constant?
_____________
E. How are the concentration values of the other two substances related?
F. Now, pick out two acidic solutions and two basic solutions from the previous chart. Indicate which is higher, the
H3O+ concentration or the OH- concentration.
Acidic/basic/neutral
solution
Which is higher, H3O+ or OH-?
Acidic
Acidic
Basic
Basic
2
Go to: phet.colorado.edu  “Play with simulations”  Acid-Base Solutions  Click play button
Part 1: Procedure
1. The lab has 2 tools that allow you to test for pH values: A probe
, and pH paper
. Use each one by dipping it
into the solution to be tested. Try all the given types of solutions and fill in the Data Chart with the pH value 0-14.
2. The circuit with a battery and bulb as shown:
is the tool used to test for conduction of a solution. By dipping the
wire leads into the solution, the bulb with either remain unlit, be dimly lit, be somewhat bright or very bright. Test
each solution and record your observation for the bulbs brightness in the chart below.
Part 1: Data
pH Value from Color & pH Value
Probe
from pH Paper
Observations from Circuit Tool
Describe the brightness
Part 1: Analysis
1. What pH value range is observed: a. for acids?______________b. for bases?____________
2. Why are some solutions better conductors of electricity?
3
Go to: phet.colorado.edu  “Play with simulations”  Reactants, Products, and Leftovers  Click play
button
Directions:
1. Use Reactants, Products, and Leftovers simulation to create your own sandwiches and then see how many
sandwiches you can make with different amounts of ingredients.
Test your learning:
2. a. Predict (without using the sim) how many
cheese sandwiches, as defined by the picture to
the right, you can make if you have 6 pieces of
bread and 4 slices of cheese.
YOUR ANSWER:
Then, use the sim to check your answer and make any corrections.
3. a. Predict what would change about your number
of sandwiches and thinking if you had the same 6
pieces of bread and 4 slices of cheese, but the
sandwich is made like the picture on the right?
YOUR ANSWER:
Check your prediction using the sim and make any changes.
4. Why did the number of sandwiches change even though the amounts of ingredients were the same? Research
what “limiting reactant” means and then write a description in your own words:
YOUR ANSWER:
5. A tricycle factory gets a shipment with 400 seats and 600 wheels. Use your ideas about Limiting Reactants to
explain how you would figure out how many tricycles can be made.
YOUR ANSWER:
Relate the model to Chemistry: Click on “Molecules” below. Explore how many molecules on the reactants side it
takes to build the number of molecules on the products side. Try this out with water, ammonia, and methane. Write down
a few observations:
YOUR OBSERVATIONS:
5
3
5
5
3
5