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Learn about the process of water purification through sedimentation, filtration, and distillation to remove impurities like soluble, insoluble, and microorganisms. Discover the importance of clean water and methods for purifying water effectively.
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04/05/2010 (Day 3) WELCOME http://plkclscmc-timothy.viviti.com/
Chapter 5 The wonderful solvent - WATER Solvent – 溶劑 A liquid that many substances can dissolve in it.
Impurities (P.55) 3 types of impurities: - soluble - insoluble - micro-organisms
Impurities (P.55) - soluble impurities??? - insoluble impurities??? - micro-organism???
Check-point 1 (P.57) 1. (a) Water is very important to all living things. Without water, living things will _________. die 1. (b) The demand for clean water is very high because water has many different __________. uses
How to remove impurities from water (P.58) The process of cleaning water is called purification.
How to remove impurities from water (P.58) 3 different methods remove different types of impurities. Sedimentation 沉積法 Filtration 過濾法 Distillation 蒸餾法
Sedimentation 沉積法 (P.59) • Remove large and insoluble impurities from water.
Experiment 5.1(P.60) • Removing large solid impurities by sedimentation 1. Solid particles in water slowly sink to the bottom of the beaker.
Experiment 5.1(P.60) • Removing large solid impurities by sedimentation top 2. The ________ portion of water is clearer.
Experiment 5.1(P.61) • Removing large solid impurities by sedimentation Alum(明礬) – AluminiumSulphate
Experiment 5.1(P.61) • Removing large solid impurities by sedimentation 3.(a) Water in the top portion becomes clearer. 3.(b) Alum makes the solid impurities to settle more quickly.
Experiment 5.1(P.61) • DISCUSSION Q: Is the water purified by this method safe to drink? Why? A: No. It is because the water may contain soluble impurities and micro-organisms.
Filtration 過濾法 (P.61) • Remove fine solid impurities.
Experiment 5.2(P.62) • II. Using the filter paper
HOMEWORK Revision Exercise P.50 Part A and B WORKBOOK Due date: 5-5-2010