Chemistry 121

  

CHEM 121 Data Analysis Report

Learning Objectives

Measure pH levels at different concentrations of acids and bases

Compare the effect of dilutions/concentration on strong and weak acids and bases

Plot the change in pH at different concentrations for the acid and for the base on line graphs (not on bar graphs)

Plot strong and weak acid data on the same graph

Plot strong and weak base data on the same graph

Using the graphed results, Interpret the effect of dilution on pH for acids and bases

INSTRUCTIONS

Plan to set aside 8-12 hours to complete this activity. It involves orientation to the chemistry simulation, running the simulation, collecting screenshots of every result, plotting the data that you collect, and answering a set of questions about the data.

*Go to the Acid-Base Solution Simulation at PhET Simulations.

https://phet.colorado.edu/en/simulation/acid-base-solutions

 

See the image below for an overview of the functions in the Acid Base Solutions simulation.

CHEM 121 Data Analysis Report

Learning Objectives

Measure pH levels at different concentrations of acids and bases

Compare the effect of dilutions/concentration on strong and weak acids and bases

Plot the change in pH at different concentrations for the acid and for the base on line graphs (not on bar graphs)

Plot strong and weak acid data on the same graph

Plot strong and weak base data on the same graph

Using the graphed results, Interpret the effect of dilution on pH for acids and bases

INSTRUCTIONS

Plan to set aside 8-12 hours to complete this activity. It involves orientation to the chemistry simulation, running the simulation, collecting screenshots of every result, plotting the data that you collect, and answering a set of questions about the data.

*Go to the Acid-Base Solution Simulation at PhET Simulations.

https://phet.colorado.edu/en/simulation/acid-base-solutions

See the image below for an overview of the functions in the Acid Base Solutions simulation.

https://phet.colorado.edu/sims/html/acid-base-solutions/latest/acid-base-solutions_en.html

*Go to the My Solution activity (right side icon)

**Retain default Views > Molecules (Solvent view is an optional addition in the Molecules view)

**You will be selecting Tools of the pH meter as well as the pH paper throughout your data collection session

Step 1. Use the yellow Reset icon (lower right) to set the Acid-Base Solution activity to default

Step 2. Place the pH reader/sensor into the container, just to the point where it records a value (that is, it is no longer blank). Or, alternatively, select the pH paper tool and place it into the container for it to register a color. Compare the color to the pH color strip.

Step 3. Move the Solution Strength toggle to “Strong.” The slide option will disappear. Or, when ready to record data for the “Weak” solution in Table 1, then Reset and move Solution > Strength to “Weak” and slide slider all the way left to “weaker.”

Step 4. Set each concentration to a value in the range indicated in parentheses in the first column of Table 1.

Step 5. Record the measured pH for each concentration in Table 1

Step 6. Record the pH paper color and the associated number for each concentration in Table 1

Step 7. Provide a screenshot in your report for each concentration level for strong and weak solutions (TOTAL = 12 screenshots). Your screenshot can be either of the pH meter or of the pH paper color

TABLE 1. Data for CHEM 121

Solution

(choose a concentration within the range in parentheses)

Concentration (moles/liter)

(enter chosen concentration below)

pH

pH paper color and number

Number of H3O+ ions (count them in the magnifying class)

Strong Acid #1 (0.005 – 0.008)

Strong Acid #2 (0.05 – 0.08)

Strong Acid #3 (0.5 — 0.8)

Weak Acid #1 (0.005 – 0.008)

Weak Acid #2 (0.05 – 0.08)

Weak Acid #3 (0.5 — 0.8)

Solution

(choose a concentration within the range in parentheses)

Concentration (moles/liter)

(enter chosen concentration below)

pH

pH paper color

Number of OH- ions

(count them in the magnifying class)

Strong Base #1 (0.005 – 0.008)

Strong Base #2 (0.05 – 0.08)

Strong Base #3 (0.5 — 0.8)

Weak Base #1 (0.005 – 0.008)

Weak Base #2 (0.05 – 0.08)

Weak Base #3 (0.5 — 0.8)

Line Graphs (for example, scatterplot option in Excel)

Submit the two plots below as part of your report

Graph A.

Plot Concentration (mol/L) (on X axes) and pH (on y axes)

for each strong acid

Graph A. Plot Concentration (mol/L) (on X axes) and pH (on y axes) for each weak acid

Graph B. Plot Concentration (mol/L) (on X axes) and pH (on y axes) for each strong base

Graph B. Plot Concentration (mol/L) (on X axes) and pH (on y axes) for each weak base

***********SEE NEXT PAGE FOR TEMPLATE of YOUR FINAL DATA ANALYSIS REPORT************

DATA ANALYSIS FINAL REPORT TEMPLATE

TOTAL POINTS = 100 POINTS

NAME________________

DATE_________________

Chemistry of the Modern World CHEM 121

CONTENT of Data Analysis Report (Use the format below for your Final Report)

DATA PRESENTATION SECTION

Complete Table 1. Data for CHEM 121 TOTAL TABLE 1: 48 POINTS

(insert here)

TABLE 1. Data for CHEM 121

Solution

(choose a concentration within the range in parentheses)

Concentration (moles/liter)

(enter chosen concentration below)

pH

pH paper color and number

Number of H3O+ ions (count them in the magnifying class)

Strong Acid #1 (0.005 – 0.008)
	Strong Acid #2 (0.05 – 0.08)
	Strong Acid #3 (0.5 — 0.8)
	Weak Acid #1 (0.005 – 0.008)
	Weak Acid #2 (0.05 – 0.08)
	Weak Acid #3 (0.5 — 0.8)

TABLE 1. Data for CHEM 121

Solution

(choose a concentration within the range in parentheses)

Concentration (moles/liter)

(enter chosen concentration below)

pH

pH paper color and number

Number of OH- ions (count them in the magnifying class)
Strong Base #1 (0.005 – 0.008)
	Strong Base #2 (0.05 – 0.08)
	Strong Base #3 (0.5 — 0.8)
	Weak Base #1 (0.005 – 0.008)
	Weak Base #2 (0.05 – 0.08)
	Weak Base #3 (0.5 — 0.8)

Provide a screenshot in your report for each concentration level (12 screenshots total). Your screenshot can be either of the pH meter or of the pH paper color, either is fine. Insert here.

1 POINT EACH for 12 SCREENSHOTS = 12 POINTS

Strong Acid #1 (0.005 – 0.008)

(Insert screenshot)

Strong Acid #2 (0.05 – 0.08)
(Insert screenshot)
Strong Acid #3 (0.5 — 0.8)
(Insert screenshot)

Weak Acid #1 (0.005 – 0.008)
(Insert screenshot)
Weak Acid #2 (0.05 – 0.08)
(Insert screenshot)
Weak Acid #3 (0.5 — 0.8)
(Insert screenshot)

Strong Base #1 (0.005 – 0.008)

(Insert screenshot)
Strong Base #2 (0.05 – 0.08)
(Insert screenshot)
Strong Base #3 (0.5 — 0.8)
(Insert screenshot)

Weak Base #1 (0.005 – 0.008)
(Insert screenshot)
Weak Base #2 (0.05 – 0.08)
(Insert screenshot)
Weak Base #3 (0.5 — 0.8)
(Insert screenshot)

GRAPHS

Plot Concentration (mol/L) (on X axes) and pH (on y axes)

Line Graph A Strong vs Weak Acid

(insert here)

Line Graph B Strong vs Weak Base

(insert here)

10 POINTS EACH for 2 LINE GRAPHS = 20 POINTS

SHORT ANSWER SECTION TOTAL = 20 POINTS

1. Compare and contrast the line graphs between strong and weak solutions (4 POINTS)

2. Compare and contrast the line graphs between acids and bases (4 POINTS)

3. Compare and contrast the number of hydronium ions (H3O+) (or hydronium ion concentration) [for acids] between strong and weak solutions (4 POINTS)

4. Compare and contrast the number of hydroxide (OH-) ions [for bases] between strong and weak solutions (4 POINTS)

5. Concluding comments (Share what you have learned about acids and bases by conducting this simulation) (4 POINTS)