Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Matter: Anything that occupies space and has mass is called matter. It is made up of tiny particles called molecules.
Solute: The substance that dissolves in a liquid to form a solution is called a solute. For example, Salt () or Sugar ().
Solvent: The liquid in which a solute dissolves is called a solvent. Water () is the most common solvent.
Solution: A clear, homogeneous mixture formed when a solute dissolves completely in a solvent is called a solution.
Universal Solvent: Water () is known as the 'Universal Solvent' because it can dissolve a wide variety of substances.
Solubility: The ability of a substance to dissolve in a given solvent is called its solubility. It often increases with an increase in temperature.
Saturated Solution: A solution in which no more solute can be dissolved at a given temperature is called a saturated solution.
Intermolecular Spaces: When a solute like salt is added to water, the salt particles occupy the empty spaces between the molecules. This is why the volume of the solution does not increase significantly when a small amount of solute is added.
📐Formulae
💡Examples
Problem 1:
If you add of sugar to of water () and stir until it disappears, identify the solute, solvent, and the resulting mixture.
Solution:
Solute: Sugar; Solvent: Water (); Mixture: Sugar Solution.
Explanation:
Sugar is the substance being dissolved (solute), water is the medium doing the dissolving (solvent), and the final uniform mixture is the solution.
Problem 2:
Explain why the water level in a beaker does not rise significantly when a spoonful of salt () is dissolved in it.
Solution:
The particles occupy the intermolecular spaces of .
Explanation:
In a liquid like , there are small gaps between the molecules called intermolecular spaces. The tiny particles of the solute () break down and fit into these gaps instead of pushing the water molecules upward.
Problem 3:
How can you dissolve more sugar in a saturated sugar solution?
Solution:
By increasing the temperature of the solution.
Explanation:
Heating the solvent () increases the kinetic energy of the molecules, creating more space and allowing more solute particles to be absorbed, thus increasing solubility.