7.6.E: investigate and model how temperature, surface area, and agitation affect the rate of dissolution of solid solutes in aqueous solutions.

Investigate, Model

HOW TEMPERATURE, SURFACE AREA, AND AGITATION AFFECTS THE RATE OF DISSOLUTION OF SOLID SOLUTES IN AQUEOUS SOLUTIONS

Including, but not limited to:

• Rate of dissolution – the length of time it takes for a certain amount of solute to dissolve in a solution

• Temperature – average kinetic energy of particles in a substance

  • Test the rates of dissolution of sugar in cold water, room temperature water, and hot water.

    • The more kinetic energy – the faster the particles move. 

    • Increased temperature will increase the rate of reaction due to the increased kinetic energy.

  • Create a model to explain how temperature affects the rate of dissolution of the sugar particles. 

• Surface area – the measure of how much exposed area that a solid object has

  • Test the rates of dissolution of a whole sugar cube, a broken-up sugar cube, and the same mass of granulated sugar in water.

    • When the sugar particles are clumped together in a cube, many of the particles are surrounded by other sugar particles.

      • Particles will only dissolve when exposed to water.

    • More surface area will increase the rate of reaction due to the increased exposure to particles.

  • Create a model to explain how surface area effects the rate of dissolution of the sugar particles.

• Agitation – put into motion by shaking or stirring (to achieve mixing)

  • Test how the rates of dissolution of granulated sugar in water are affected by letting it settle, stirring it slowly, and then stirring it faster.

    • When the sugar particles are moved around, more particles are exposed to the water.

      • Particles will only dissolve when exposed to water.

  • Create a model to explain how agitating affects the rate of dissolution of the sugar particles.