Effects in Dissolution
What is a “solute” in a solution?
The substance that gets dissolved.
How does increasing temperature affect the rate of dissolution for most solids?
It increases the rate of dissolution.
What does “surface area” mean in dissolution?
The amount of exposed area of the solute.
What does agitation mean?
Stirring or shaking.
What happens at the molecular level when salt dissolves in water?
Water molecules surround and pull apart the sodium and chloride ions.
What is a “solvent”?
The substance that dissolves the solute (often water).
What happens to gas solubility when temperature increases?
It decreases (gases dissolve less in warm liquids).
Which dissolves faster: a sugar cube or granulated sugar?
Granulated sugar (more surface area).
How does stirring affect the rate of dissolution?
It speeds it up.
Why do polar substances dissolve other polar substances?
Because opposite charges attract.
What do we call a uniform mixture of two or more substances?
A solution.
Why does sugar dissolve faster in hot tea than cold tea?
Heat gives molecules more energy to move and break solute bonds.
Why does crushing a solid increase its rate of dissolution?
It increases surface area for solvent contact.
Why does stirring help solutes dissolve faster?
It moves solvent particles around, bringing them into contact with solute.
What does “like dissolves like” mean?
Polar dissolves polar, nonpolar dissolves nonpolar.
What happens to the particles of a solute when it dissolves?
They spread evenly and become surrounded by solvent molecules.
What type of solution forms when no more solute can dissolve at a given temperature?
A saturated solution.
Give an example of expanding surface area in real life.
Crushing ice cubes to make a drink cool faster.
What happens if you don’t stir a solute in water?
It dissolves more slowly.
How do solvent molecules interact with solute molecules?
They surround and separate them evenly in the mixture.
Why is water called the “universal solvent”?
Because it can dissolve many substances due to its polarity.
Explain how temperature affects the solubility curve of a solid.
As temperature increases, the solubility curve rises (more solute dissolves).
Explain how particle size affects dissolving rate.
Smaller particles dissolve faster due to increased surface contact.
Describe how agitation, surface area, and temperature together affect dissolving.
All increase particle collisions and speed up dissolution.
Draw or describe what’s happening at the molecular level in a saltwater solution.
Water molecules (polar) surround Na⁺ and Cl⁻ ions, breaking their bonds and spreading them evenly