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How does the molecular weight of a solute impact its diffusion rate in a solvent? Provide an experimental design and data analysis to support your answer.

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The molecular weight of a solute has a significant impact on its diffusion rate in a solvent. In general, solutes with lower molecular weights tend to diffuse more quickly than those with higher molecular weights. This is because smaller molecules can move more easily through the solvent, encountering less resistance from the solvent molecules. This relationship can be described by the Stokes-Einstein equation:D = kT /  6r where D is the diffusion coefficient, k is Boltzmann's constant, T is the temperature,  is the viscosity of the solvent, and r is the radius of the solute molecule. As the molecular weight of the solute increases, the radius of the solute molecule also increases, leading to a decrease in the diffusion coefficient.Experimental Design:1. Objective: To investigate the relationship between the molecular weight of a solute and its diffusion rate in a solvent.2. Materials:   - Solutes with varying molecular weights  e.g., sucrose, sodium chloride, and potassium permanganate    - Solvent  e.g., distilled water    - Beakers   - Graduated cylinders   - Stopwatch   - Analytical balance   - Thermometer   - Spectrophotometer  optional 3. Procedure:   a. Measure equal volumes of the solvent  e.g., 100 mL  using a graduated cylinder and pour into separate beakers.   b. Measure equal masses  e.g., 1 g  of each solute using an analytical balance.   c. Record the temperature of the solvent using a thermometer.   d. At the same time, add each solute to a separate beaker of solvent and start the stopwatch.   e. Observe and record the time it takes for each solute to completely dissolve and uniformly distribute in the solvent. This can be done visually or by using a spectrophotometer to measure the absorbance of the solution at regular intervals.   f. Repeat the experiment at least three times for each solute to ensure accuracy and consistency.4. Data Analysis:   a. Calculate the average time it takes for each solute to dissolve and uniformly distribute in the solvent.   b. Plot a graph of molecular weight  x-axis  versus average diffusion time  y-axis  for each solute.   c. Analyze the graph to determine the relationship between molecular weight and diffusion rate. A negative correlation would indicate that as molecular weight increases, the diffusion rate decreases.The results of this experiment should demonstrate that solutes with lower molecular weights diffuse more quickly in the solvent than those with higher molecular weights, supporting the hypothesis that molecular weight impacts diffusion rate.
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