CALCULATIONS: 1. Prepare a Temperature vs Time cooling curve for each of the two trials performed with pure stearic acid. Perform a linear regression analysis on both the cooling and the freezing regions for each trial. For Trial 1, show the calculation below for determining the point of intersection between the two lines and the value for the freezing point of pure stearic acid. Identify this point on both graphs by inserting a text box and arrow. Report the average of the two freezing points.

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# Calculations:

1. **Prepare a Temperature vs Time Cooling Curve:**
   - Construct a cooling curve for each of the two trials performed with pure stearic acid.
   - Perform a linear regression analysis on both the cooling and the freezing regions for each trial.
   - **For Trial 1:**
     - Show the calculation for determining the point of intersection between the two lines.
     - Identify the value for the freezing point of pure stearic acid.
     - **Identify this point on both graphs** by inserting a text box and arrow.
   - Report the average of the two freezing points. 

**Detailed Graph Explanation**: (Assuming there would be two similar graphs based on the instruction)

- **Temperature vs Time Graph**:
  - **X-Axis**: This represents the time, possibly measured in minutes or seconds.
  - **Y-Axis**: This denotes the temperature, potentially measured in degrees Celsius or Fahrenheit.
  - **Curve Description**: 
     - The graph should show a cooling curve where the temperature of the stearic acid decreases over time.
     - Two distinct regions should be apparent in the cooling curve: a cooling region where temperature drops continuously and a freezing region where temperature remains constant or nearly constant.
  - **Linear Regression Analysis**:
    - Apply linear regression to model the cooling region with a downward-sloping line.
    - Apply another linear regression for the freezing region, which should ideally be a horizontal line if the temperature remains nearly constant.
  - **Point of Intersection**:
    - On Trial 1, calculate where these two lines intersect.
    - This intersection point indicates the freezing point of pure stearic acid for Trial 1.
    - Insert a text box and an arrow on the graph to mark this intersection point clearly.
  - **Averaging**: 
    - Repeat the procedure for the second trial.
    - Report the average of the two freezing points obtained from both trials as the final result.
Transcribed Image Text:# Calculations: 1. **Prepare a Temperature vs Time Cooling Curve:** - Construct a cooling curve for each of the two trials performed with pure stearic acid. - Perform a linear regression analysis on both the cooling and the freezing regions for each trial. - **For Trial 1:** - Show the calculation for determining the point of intersection between the two lines. - Identify the value for the freezing point of pure stearic acid. - **Identify this point on both graphs** by inserting a text box and arrow. - Report the average of the two freezing points. **Detailed Graph Explanation**: (Assuming there would be two similar graphs based on the instruction) - **Temperature vs Time Graph**: - **X-Axis**: This represents the time, possibly measured in minutes or seconds. - **Y-Axis**: This denotes the temperature, potentially measured in degrees Celsius or Fahrenheit. - **Curve Description**: - The graph should show a cooling curve where the temperature of the stearic acid decreases over time. - Two distinct regions should be apparent in the cooling curve: a cooling region where temperature drops continuously and a freezing region where temperature remains constant or nearly constant. - **Linear Regression Analysis**: - Apply linear regression to model the cooling region with a downward-sloping line. - Apply another linear regression for the freezing region, which should ideally be a horizontal line if the temperature remains nearly constant. - **Point of Intersection**: - On Trial 1, calculate where these two lines intersect. - This intersection point indicates the freezing point of pure stearic acid for Trial 1. - Insert a text box and an arrow on the graph to mark this intersection point clearly. - **Averaging**: - Repeat the procedure for the second trial. - Report the average of the two freezing points obtained from both trials as the final result.
### Cooling Experiment - Temperature vs. Time Data

This dataset illustrates temperature measurements over time during a cooling experiment for two different substances labeled as "SA" and "Pure SA." The results are recorded at intervals, showcasing the cooling curves for each.

#### SA Data

| Temperature (°C) | Time (s) |
|------------------|----------|
| 85.0             | 0        |
| 80.5             | 30       |
| 78.8             | 60       |
| 76.5             | 90       |
| 74.5             | 120      |
| 72.5             | 150      |
| 71.8             | 180      |
| 69.0             | 210      |
| 68.4             | 240      |
| 68.1             | 270      |
| 68.1             | 300      |
| 68.1             | 330      |
| 68.1             | 360      |
| 68.0             | 390      |
| 68.0             | 420      |
| 67.9             | 450      |

#### Pure SA Data

| Temperature (°C) | Time (s) |
|------------------|----------|
| 85.0             | 0        |
| 79.9             | 30       |
| 76.9             | 60       |
| 74.5             | 90       |
| 72.3             | 120      |
| 70.4             | 150      |
| 69.0             | 180      |
| 68.2             | 210      |
| 68.1             | 240      |
| 68.1             | 270      |
| 68.0             | 300      |
| 67.9             | 330      |
| 67.9             | 360      |
| 67.9             | 390      |
| 67.9             | 420      |

### Analysis

- Both datasets show a decrease in temperature over time.
- There's a marked period where the temperature remains relatively constant, indicating the phase change or freezing point.
- For SA, the freezing period appears to start from 71.8°C and maintain around 68.1°C.
- For Pure SA, similar
Transcribed Image Text:### Cooling Experiment - Temperature vs. Time Data This dataset illustrates temperature measurements over time during a cooling experiment for two different substances labeled as "SA" and "Pure SA." The results are recorded at intervals, showcasing the cooling curves for each. #### SA Data | Temperature (°C) | Time (s) | |------------------|----------| | 85.0 | 0 | | 80.5 | 30 | | 78.8 | 60 | | 76.5 | 90 | | 74.5 | 120 | | 72.5 | 150 | | 71.8 | 180 | | 69.0 | 210 | | 68.4 | 240 | | 68.1 | 270 | | 68.1 | 300 | | 68.1 | 330 | | 68.1 | 360 | | 68.0 | 390 | | 68.0 | 420 | | 67.9 | 450 | #### Pure SA Data | Temperature (°C) | Time (s) | |------------------|----------| | 85.0 | 0 | | 79.9 | 30 | | 76.9 | 60 | | 74.5 | 90 | | 72.3 | 120 | | 70.4 | 150 | | 69.0 | 180 | | 68.2 | 210 | | 68.1 | 240 | | 68.1 | 270 | | 68.0 | 300 | | 67.9 | 330 | | 67.9 | 360 | | 67.9 | 390 | | 67.9 | 420 | ### Analysis - Both datasets show a decrease in temperature over time. - There's a marked period where the temperature remains relatively constant, indicating the phase change or freezing point. - For SA, the freezing period appears to start from 71.8°C and maintain around 68.1°C. - For Pure SA, similar
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