Water & solution SCIENCE FORM 2
Download as PPTX, PDF19 likes33,010 views
The document provides information about water and solutions. It discusses several key points in 3 sentences: Water covers about two-thirds of the Earth's surface and has unique physical properties as a liquid. Pure water is colorless, odorless, and tasteless. Water can exist as a solid, liquid, or gas and its state depends on temperature, with freezing and boiling points occurring at 0°C and 100°C respectively. The document then covers solubility and solutions, discussing solutes, solvents, saturated and unsaturated solutions, and factors that affect solubility. It also addresses acids, alkalis, and neutralization reactions. Finally, it summarizes several methods for purifying water, including sedimentation
Water & solution SCIENCE FORM 2
- 1. SCIENCE FORM 2 WATER & SOLUTION By: Nur Hidayah Taib SMK Lembah Bidong ‘12 Facts: 2/3 of earth’s surface is covered with water.
- 2. Physical characteristics of water PURE WATER IS COLOURLESS, ODOURLESS, T ASTELESS LIQUID
- 3. Physical characteristics of water STATE OF WATER Sublimation Melting Boiling Freezing Condensation
- 4. Physical characteristics of water FREEZING AND BOILING POINT OF WATER Freezing point: the temperature at Boiling point: temperature when water which water freeze to form ice. boils to produce steam. Heat is released KINETIC THEORY Heat is absorbed
- 5. The effect of impurities on the physical characteristics of water. • Freezing point and melting point of water are same. • Impurities increase the boiling point of water. • Impurities lower the freezing point of water.
- 6. The composition of water O H H Chemical formula: H2O
- 7. ELECTROLYSIS OF WATER • Electrolysis is a process of to break down a compound into simpler substances. O2 H2 Water + dilute sulphuric acid cathode anode A
- 9. EVAPORATION BOILING SIMILARITIES Liquid gas Absorps heat DIFFERENCES Occurs at any temperature Occurs only at boiling point Occurs only on the exposed Occurs throughout the liquid surface of a liquid No bubbles are formed Bubbles formed throughout the liquid Absorbs heat from the Requires heat supplied by a source surroundings when water such as a lighted bunsen burner turns into gas
- 10. SOLUTION AND SOLUBILITY SOLUTE Substances that dissolves SOLVENT Substances that dissolve the solute
- 11. Concentrated solution It refers to a solution in which much of the water has been removed. Dilute solution to make (a liquid) thinner or weaker by the addition of water or the like.
- 12. Saturated solution solution in which the maximum amount of solvent has been dissolved. Any more solute added will sit as crystals on the bottom of the container.
- 13. SUSPENSION Solution suspension homogeneous Non-homogeneous Clear/transparent Cloudy/translucent Contains one or more soluble substances Contains one ore more insoluble subtances Contains substances that cannot be Contains substances that easily be easily separated separated
- 14. SOLUBILITY The maximum amount of a solute which can dissolve in a given amount of solvent at a fixed temperature. THE RATE OF DISSOLVING Time taken for the dissolving process, from the time the solute is added to the solvent until it has completely dissolved.
- 15. Stirring Size of FACTORS THAT AFFECT THE Volume of SOLUBILITY OF solvent solute SOLUTE IN WATER Temperature
- 17. Substances that do not dissolve in water may be soluble in ORGANIC SOLVENTS ORGANIC USES SOLVENTS CHLOROFORM •Stick plastics letter & numbers on the number plats of vehicle BENZENE •To stick piece of rubber on a punctured tyre ALCOHOL •Prepare shellac •Dissolve iodine to make antiseptic AMYL ACETATE •Remove lipstick stain TURPENTINE •Remove paint from the floor LIME JUICE •Remove rust
- 19. ACIDS Taste: Sour. Touch: Like water. Tested with litmus paper: Turn blue litmus red. pH value: From 0 to less than 7. Reaction with metals: Form hydrogen and a salt. Reaction with carbonates: Form a salt, water and carbon dioxide. Reaction with ammonium compounds: No reaction. NEUTRAL ALKALIS Taste: Bitter. Touch: Soapy. Tested with litmus paper: Turn red litmus blue. pH value: From above 7 to 14. Reaction with metals: No reaction. Reaction with carbonates: No reaction. Reaction with ammonium compounds: Give off ammonia gas
- 20. NEUTRALISATION e.g: NaOH + HCl NaCl + H2O
- 21. Shampoos toothpaste Hair conditioner APPLICATIONS OF NEUTRALISATION bicarbonate powder slaked lime
- 22. SEDIMENTATION FILTRATION CHLORINATION OZONE DISTILLATION BOILING UV LIGHT
- 23. UV LIGHT •As the water passes through this vessel, microorganisms are exposed to intense ultraviolet light energy which causes damage to genetic molecules (i.e. nucleic acids: DNA or RNA) needed for reproductive functions. •This damage prevents the microorganism from multiplying or replicating in a human or animal host. •Because the microorganism cannot multiply, no infection can occur. Disinfection of water is achieved when UV light causes microbial inactivation.
- 27. WATER PURIFICATION 1. Water from the rivers are channel into the reservoir. 2. In the Aeration Tank bad smells will be aired and removed from the water. 3. Alum and Lime are added into the water in the coagulation tank. Alum will make particles join together to form larger particles while lime will decrease the acidity of water. 4. In the mixing tank, alum and lime will be evenly distributed in the water the water. 5. The water travels into the sedimentation tank so that large particles will sediment to the bottom. 6. Lighter particles which floats on the water will flow into the filtration tank, suspended particles will be filtered. 7. Clean water will then be stored at the storage tank. In the storage tank, chlorine and fluorine will be added in the water.
- 28. WATER POLLUTION