If you were asked to dissolve a solid into an aqueous solution, how could you speed this process up? How could you slow it down? Listed
below are a number of possible ways to alter the rate of this process. Place them in the proper category. If you need help, think about putting
sugar in your tea.
Increases Rate
:: Crush the solute into a powder.
Decreases Rate
:: Cool the solvent. :: Leave the solution untouched.
:: Warm the solvent.
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No Rate Change
:: Add the solute quickly.
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The Correct Answer and Explanation is :
To understand how to dissolve a solid in an aqueous solution effectively, it’s essential to recognize factors that can either increase or decrease the rate of dissolution. Here’s how various methods affect the rate:
Increases Rate:
- Crush the solute into a powder: Reducing the size of the solid increases its surface area, allowing more solvent to interact with the solute at once. A larger surface area speeds up the dissolution process because more solute particles are exposed to the solvent, facilitating quicker interactions and breaking apart of the solute.
Decreases Rate:
- Cool the solvent: Lowering the temperature decreases the kinetic energy of the solvent molecules, leading to slower movement. This reduced molecular motion results in fewer collisions between the solute and solvent, slowing the dissolution process.
- Leave the solution untouched: Stirring the solution helps distribute the solute more evenly throughout the solvent, increasing the contact between solute and solvent. Leaving it untouched prevents this mixing, leading to slower dissolution as the solute remains localized.
Increases Rate:
- Warm the solvent: Heating the solvent increases the kinetic energy of the molecules, causing them to move faster. This enhances the rate of collisions between solute and solvent molecules, promoting faster dissolution.
No Rate Change:
- Add the solute quickly: This action does not inherently change the rate of dissolution. While adding the solute quickly might momentarily create a large concentration of solute in a specific area, it does not influence the inherent properties of the solvent or solute that dictate the rate of dissolution.
Conclusion:
In summary, to speed up the dissolution of a solid into a solution, you can increase the surface area of the solute by crushing it and raise the temperature of the solvent. Conversely, cooling the solvent or leaving the solution undisturbed will slow down the process. Understanding these principles not only applies to everyday situations like dissolving sugar in tea but also has broader implications in various scientific and industrial contexts.