Based on the following data, is this iron thiocyanate reaction endothermic or exothermic?:  Fe3+(aq)    +    SCN−(aq)   ⇌   FeSCN2+(aq) [colorless]         [colorless]         [blood-red color] After being submreged in a hot water bath, the solution was colorless. After being submerged in an ice bath, the solution turned dark red in color.

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Based on the following data, is this iron thiocyanate reaction endothermic or exothermic?:

 Fe3+(aq)    +    SCN−(aq)   ⇌   FeSCN2+(aq)

[colorless]         [colorless]         [blood-red color]

After being submreged in a hot water bath, the solution was colorless.

After being submerged in an ice bath, the solution turned dark red in color. 

### Chemical Equilibrium Reaction Observation

**Chemical Equation:**

\[ \text{Fe}^{3+} (aq) + \text{SCN}^- (aq) \leftrightarrows \text{FeSCN}^{2+} (aq) \]
*Blood-red color*

This reaction demonstrates the concept of chemical equilibrium with a visible color change. Below are the observations from different experimental conditions:

#### Table 1. Equilibrium Response Observations

| Test Tube | Color Observation         | Reaction Response    |
|-----------|---------------------------|----------------------|
| **Test tube 1 - Control**            | Light red            | Select a response  |
| **Test tube 2 - Add KSCN (aq)**      | Slightly darker red  | Towards reactants  |
| **Test tube 3 - Add Fe(NO₃) (aq)**   | Darker red           | Towards reactants  |
| **Test tube 4 - Add NaF (s)**        | No color             | Towards products   |
| **Test tube 5 - Hot water bath**     | Almost colorless     | Towards products   |
| **Test tube 6 - Ice bath**           | Slightly darker red  | Towards reactants  |

**Details:**

- **Test tube 1 (Control):** The solution shows a light red color, serving as the baseline for further tests.
  
- **Test tube 2 (Add KSCN):** Adding potassium thiocyanate results in a slightly darker red color, indicating a shift towards the reactants.

- **Test tube 3 (Add Fe(NO₃)):** The addition of iron(III) nitrate darkens the red color further, suggesting a shift towards the reactants as more Fe³⁺ ions are available.

- **Test tube 4 (Add NaF):** The solution becomes colorless due to the formation of a complex that consumes Fe³⁺, shifting equilibrium towards the products.

- **Test tube 5 (Hot water bath):** Heating the solution makes it almost colorless, indicating a shift towards the products, likely due to increased kinetic energy favoring the reaction in that direction.

- **Test tube 6 (Ice bath):** Cooling the solution results in a slightly darker red color, indicating a shift towards the reactants due to decreased kinetic energy.

These observations highlight how changes in concentration and temperature can influence the position of equilibrium
Transcribed Image Text:### Chemical Equilibrium Reaction Observation **Chemical Equation:** \[ \text{Fe}^{3+} (aq) + \text{SCN}^- (aq) \leftrightarrows \text{FeSCN}^{2+} (aq) \] *Blood-red color* This reaction demonstrates the concept of chemical equilibrium with a visible color change. Below are the observations from different experimental conditions: #### Table 1. Equilibrium Response Observations | Test Tube | Color Observation | Reaction Response | |-----------|---------------------------|----------------------| | **Test tube 1 - Control** | Light red | Select a response | | **Test tube 2 - Add KSCN (aq)** | Slightly darker red | Towards reactants | | **Test tube 3 - Add Fe(NO₃) (aq)** | Darker red | Towards reactants | | **Test tube 4 - Add NaF (s)** | No color | Towards products | | **Test tube 5 - Hot water bath** | Almost colorless | Towards products | | **Test tube 6 - Ice bath** | Slightly darker red | Towards reactants | **Details:** - **Test tube 1 (Control):** The solution shows a light red color, serving as the baseline for further tests. - **Test tube 2 (Add KSCN):** Adding potassium thiocyanate results in a slightly darker red color, indicating a shift towards the reactants. - **Test tube 3 (Add Fe(NO₃)):** The addition of iron(III) nitrate darkens the red color further, suggesting a shift towards the reactants as more Fe³⁺ ions are available. - **Test tube 4 (Add NaF):** The solution becomes colorless due to the formation of a complex that consumes Fe³⁺, shifting equilibrium towards the products. - **Test tube 5 (Hot water bath):** Heating the solution makes it almost colorless, indicating a shift towards the products, likely due to increased kinetic energy favoring the reaction in that direction. - **Test tube 6 (Ice bath):** Cooling the solution results in a slightly darker red color, indicating a shift towards the reactants due to decreased kinetic energy. These observations highlight how changes in concentration and temperature can influence the position of equilibrium
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