Chapter: 08. Some Properties Of Water
I. Multiple Choice Questions
II. Fill in the Blanks
III. True/False Questions
IV. Explanation of Terms
Solution: A solution is a mixture where one substance completely dissolves in another substance at a particular temperature, creating a clear mixture. Insoluble substances: These are substances that do not dissolve in a solvent, meaning they will not mix completely and remain separate in the liquid. V. Short Answer Questions
The three different forms of water are solid (ice), liquid (water), and gas (water vapour). Two ways to make sugar dissolve faster in water are by heating the water (solvent) and by stirring the sugar (solute) into the water. When water is heated in a pot until steam appears, the liquid water absorbs enough heat to change its state. This process is called evaporation, where the liquid water turns into a gas (water vapour), which is visible as steam rising from the pot. VI. Diagram-Based Question
a) Process A is Melting, and Process B is Evaporation. b) Process C is Condensation, and Process D is Solidification (or Freezing). c) The snowflake symbol indicates processes that involve cooling (C and D), as cooling removes heat, causing substances to condense or freeze. VII. Long Answers
Water is often called the “universal solvent” because it has a unique ability to dissolve a very large number of different substances. This property makes water essential for many natural processes, such as transporting nutrients in plants and animals, and for various daily uses like cleaning and cooking, as it can effectively dissolve many things we want to mix or remove. Whether an object floats or sinks depends on how much water it pushes away compared to its own weight, which is based on Archimedes’ principle. A wooden block floats because it displaces a weight of water that is greater than its own weight, making it less dense than water. A metal key sinks because it displaces a weight of water that is less than its own weight, meaning it is denser than the water it pushes aside. VIII. Identifying and/or Differentiate Concepts/Processes
Solute: The substance that gets dissolved in a mixture (e.g., sugar in lemonade).
Solvent: The substance that does the dissolving in a mixture (e.g., water in lemonade). Melting: The process where a solid changes into a liquid, usually caused by heating.
Freezing: The process where a liquid changes into a solid, usually caused by cooling. 
Answer key