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Separation Techniques (Ri Tong) - Coggle Diagram
Separation Techniques (Ri Tong)
WHY?
Mixtures consist of 2 or more substances which are mixed without being chemically bonded together
The purity of substances is important in our daily lives
To obtain useful substances
Air contains useful substances such as oxygen and nitrogen which have their respective applications
Seawater contains table salt for cooking or preserving foods
Reservoirs provide freshwater for drinking
Crude oil contains useful fuels such as petrol and kerosene
To study the properties
Chemists need pure substances to study their chemical and physical properties
To avoid unwanted consequences
Impurities in drugs and food can produce unwanted side effects, so purity is very important in the pharmaceutical industry
Mixtures can be separated easily into pure substances by purification techniques
Purification techniques are classified as physical methods because it only separates one substance from the other without involving chemical damage
The Four National Taps
Water is a limited natural resource in Singapore. To protect the country's sovereignty, Singapore needs to have more reliable water resources.
Singapore plans to become self-sufficient in its water supply from the four important sources called The Four National Taps
Water catchment areas
Desalinated water
Imported water from other countries
NEWater
In order to produce pure and safe drinking water from rainwater, seawater and used water, different separating techniques are used to remove impurities from the respective water resources.
SEPARATION OF
SOLID-SOLID
MIXTURES
Sublimation
WHAT?
Examples of sublimed substances
Dry ice
Iodine crystals
Naphthalene (mothballs)
Used when one of the solid substances can sublime when heating
APPLICATION
It is used in printing process that uses heat to transfer dye onto paper or fabric to produce photographic prints.
Magnetic attraction
WHAT?
Magnets are used to separate magnetic materials from non-magnetic materials in a mixture.
The magnetic materials are:
Iron
Steel
Nickel
Cobalt
E.g. Iron fillings can be separated from sulfur powder in mixture
APPLICATION
At the scrap yards, a strong electromagnet is used to salvage scrap iron and steel from other junk materials.
In mining, it is used to separate magnetic ores from none-magnetic ores.
It is used in hospitals to remove iron splinters from patient's eyes.
SEPARATION OF
SOLID-LIQUID
MIXTURES
Filtration
Used to separate an insoluble solid from water
e.g. Filtration can be used to separate chalk powder from water
Features
Filter paper
Residue
Filter funnel
Small liquids can pass through pores
Large solid particles trapped on filter paper
Filtrate
A filter paper is used to filter an insoluble solid from a liquid.