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Naomi
02/12/2025
Chemistry
Separation Techniques for Pure Substances
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•
2 Dec 2025
•
Essential Separation Methods for Mixtures and Pure Substances
Separation Techniques
Mixtures are everywhere around us - from the air we breathe to the drinks we enjoy. The brilliant thing is that because these substances aren't chemically stuck together, we can separate them using some pretty neat scientific tricks.
Evaporation is your go-to method when you want to separate a dissolved solid from its liquid. Simply heat up the mixture and watch the liquid turn to vapour, leaving the solid behind - perfect for getting salt from salt water.
Filtration works like a super-fine sieve to catch solid particles that won't dissolve. The liquid passes straight through the filter paper, but those stubborn solid bits get trapped - ideal for separating sand from water.
Simple distillation is like evaporation's clever cousin. It separates liquids from solutions by evaporating the liquid, then cooling and condensing it back in a separate container. The dissolved solid stays put whilst you collect pure liquid.
Paper chromatography reveals the hidden colours in mixtures by letting them travel up special paper at different speeds. Scientists can even calculate something called the retardation factor (Rf) to identify exactly what compounds they've separated.
Crystallisation creates beautifully organised solid structures as atoms and molecules arrange themselves in perfect patterns - think of how salt crystals form when seawater evaporates naturally.
Quick Tip: Remember that separation techniques work because different substances have different physical properties - use these differences to your advantage!
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Essential Separation Methods for Mixtures and Pure Substances
Ever wondered how scientists get pure salt from seawater or how to separate different coloured inks? Separation techniquesare the clever methods chemists use to split up mixtures and get the pure substances they need for everything from medicines to... Show more
Separation Techniques
Mixtures are everywhere around us - from the air we breathe to the drinks we enjoy. The brilliant thing is that because these substances aren't chemically stuck together, we can separate them using some pretty neat scientific tricks.
Evaporation is your go-to method when you want to separate a dissolved solid from its liquid. Simply heat up the mixture and watch the liquid turn to vapour, leaving the solid behind - perfect for getting salt from salt water.
Filtration works like a super-fine sieve to catch solid particles that won't dissolve. The liquid passes straight through the filter paper, but those stubborn solid bits get trapped - ideal for separating sand from water.
Simple distillation is like evaporation's clever cousin. It separates liquids from solutions by evaporating the liquid, then cooling and condensing it back in a separate container. The dissolved solid stays put whilst you collect pure liquid.
Paper chromatography reveals the hidden colours in mixtures by letting them travel up special paper at different speeds. Scientists can even calculate something called the retardation factor (Rf) to identify exactly what compounds they've separated.
Crystallisation creates beautifully organised solid structures as atoms and molecules arrange themselves in perfect patterns - think of how salt crystals form when seawater evaporates naturally.
Quick Tip: Remember that separation techniques work because different substances have different physical properties - use these differences to your advantage!
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Where can I download the Knowunity app?
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THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
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