SCIENCE FORM 2WATER & SOLUTION By: Nur Hidayah Taib SMK Lembah Bidong ‘12 Facts: 2/3 of earth’s surface is covered with water.
Physical characteristics of water PURE WATER IS COLOURLESS, ODOURLESS, T ASTELESS LIQUID
Physical characteristics of water STATE OF WATER Sublimation Melting Boiling Freezing Condensation
Physical characteristics of waterFREEZING AND BOILING POINT OF WATERFreezing point: the temperature at Boiling point: temperature when waterwhich water freeze to form ice. boils to produce steam. Heat is released KINETIC THEORY Heat is absorbed
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.
The composition of water O H H Chemical formula: H2O
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
EVAPORATION BOILINGSIMILARITIES Liquid gas Absorps heatDIFFERENCES 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
SOLUTION AND SOLUBILITY SOLUTE Substances that dissolves SOLVENT Substances that dissolve the solute
Concentrated solutionIt refers to a solution in which much of the water hasbeen removed. Dilute solution to make (a liquid) thinner or weaker by the addition of water or the like.
Saturated solutionsolution in which the maximum amount of solvent has beendissolved. Any more solute added will sit as crystals on the bottomof the container.
SUSPENSIONSolution suspensionhomogeneous Non-homogeneousClear/transparent Cloudy/translucentContains one or more soluble substances Contains one ore more insoluble subtancesContains substances that cannot be Contains substances that easily beeasily separated separated
SOLUBILITYThe 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.
StirringSize of FACTORS THAT AFFECT THE Volume of SOLUBILITY OF solventsolute SOLUTE IN WATER Temperature
Substances that do not dissolve in water may be soluble in ORGANIC SOLVENTSORGANIC USESSOLVENTSCHLOROFORM •Stick plastics letter & numbers on the number plats of vehicleBENZENE •To stick piece of rubber on a punctured tyreALCOHOL •Prepare shellac •Dissolve iodine to make antisepticAMYL ACETATE •Remove lipstick stainTURPENTINE •Remove paint from the floorLIME JUICE •Remove rust
ACIDSTaste: 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. NEUTRALALKALISTaste: 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
UV LIGHT•As the water passes through this vessel, microorganisms are exposed tointense ultraviolet light energy which causes damage to geneticmolecules (i.e. nucleic acids: DNA or RNA) needed for reproductivefunctions.•This damage prevents the microorganism from multiplying orreplicating in a human or animal host.•Because the microorganism cannot multiply, no infection can occur.Disinfection of water is achieved when UV light causes microbialinactivation.
WATER PURIFICATION1. 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.