Separating Mixtures Lesson 5 Extracting Salt Read the

  • Slides: 26
Download presentation
Separating Mixtures Lesson 5: Extracting Salt Read the information in this Power. Point and

Separating Mixtures Lesson 5: Extracting Salt Read the information in this Power. Point and complete the tasks in your book. Use the links for extra information

Separating Mixtures Lesson 5: Extracting Salt Mixtures can be separated by physical processes such

Separating Mixtures Lesson 5: Extracting Salt Mixtures can be separated by physical processes such as filtration, crystallisation, simple distillation, fractional distillation and chromatography. These physical processes do not involve chemical reactions. Students should be able to: • describe, explain and give examples of the specified processes of separation • suggest suitable separation and purification techniques for mixtures when given appropriate information.

Separating Mixtures Lesson 5: Extracting Salt https: //www. bbc. co. uk/bitesize/guides/zb 2 f 3

Separating Mixtures Lesson 5: Extracting Salt https: //www. bbc. co. uk/bitesize/guides/zb 2 f 3 k 7/revisi on/1 https: //www. youtube. com/watch? v=ka 6 o 5 VCPRF 8 https: //www. youtube. com/watch? v=g. IMt. Fj 2 g. Ps 8 https: //www. youtube. com/watch? v=86 WY 2 m. V 9 ji. U https: //www. youtube. com/watch? v=-XCPPB-s. BFU

Separating Mixtures Lesson 5: Extracting Salt LO: I can extract pure salt from Rock

Separating Mixtures Lesson 5: Extracting Salt LO: I can extract pure salt from Rock Salt by filtration and evaporation Starter: Which of the descriptions below describes a mixture? What is the other box describing? A Two or more different atoms that are not chemically joined B Two or more different atoms that are chemically joined

Separating Techniques Filtration – we use filtration when we want to separate particles of

Separating Techniques Filtration – we use filtration when we want to separate particles of solids from a solvent (liquid). The particles get stuck in the filter paper, and the solvent passes through.

Separating Techniques Evaporation – we use evaporation when we want to remove liquid from

Separating Techniques Evaporation – we use evaporation when we want to remove liquid from a mixture of liquid and dissolved solids. The liquid evaporates and leaves the solid behind. HEAT

Making Pure Salt Step 1: Collect and crush a small amount of rock salt

Making Pure Salt Step 1: Collect and crush a small amount of rock salt pestle rock salt Step 3: Filter the impure salt solution. test tube crushed rock salt stirring rod crushed rock salt mortar filter funnel Step 2: Dissolve the salt in 50 ml of water impurities filter paper pure salt solution impure salt solution beaker Step 4: Evaporate half the water from the pure salt solution evaporating dish gauze tripod HEAT

Now complete your worksheet • Complete your worksheet and stick it into your book

Now complete your worksheet • Complete your worksheet and stick it into your book (slide 6).

HEAT Filtration – used to separate p______ of s_____ from a s_______ (liquid). The

HEAT Filtration – used to separate p______ of s_____ from a s_______ (liquid). The p________ get stuck in the f______ p_____, and the s_______ passes through. Evaporation – used to remove l______ from a m_______ of liquid and d________ s_____. The liquid e__________ and leaves the s______ behind. HEAT

Distillation WILF: I can explain how to separate two liquids in a mixture. Starter:

Distillation WILF: I can explain how to separate two liquids in a mixture. Starter: Complete the sheet. REMEMBER – if we dissolve something it doesn’t disappear its just too small to see

Separating Liquids Separating immiscible liquids Liquids that do not mix together are described as

Separating Liquids Separating immiscible liquids Liquids that do not mix together are described as immiscible. oil + water Immiscible liquids can be separated by simply removing the top layer using a pipette.

Separating Liquids Separating miscible liquids Liquids that do mix together are described as miscible.

Separating Liquids Separating miscible liquids Liquids that do mix together are described as miscible. An example of this is water and alcohol – these two liquids mix together easily. How could you separate a mixture of miscible liquids? +

Separating Liquids Distillation The technique used to separate a liquid from a mixture is

Separating Liquids Distillation The technique used to separate a liquid from a mixture is called distillation. Distillation has three steps: 1. evaporation 2. condensation 3. collection The solution is heated so that the liquid evaporates and is turned into a gas. Everything else is left behind. The gas cools in the condenser and turns back into a liquid, which can then be collected.

Distillation

Distillation

Separating Mixtures Ls 5: Chromatography WILF: • I can identify individual dyes from mixtures

Separating Mixtures Ls 5: Chromatography WILF: • I can identify individual dyes from mixtures of different dyes Starter: Complete the sheet on distillation to recap what we learnt last lesson

Chromatography means colour-writing. Chromatography is used to separate mixtures of coloured or non-coloured substances

Chromatography means colour-writing. Chromatography is used to separate mixtures of coloured or non-coloured substances that are soluble in the same solvent. A spot of the mixture is placed on some filter paper. The solvent is soaked up the paper. The different colours separate because the more soluble substance spreads along the paper faster

Chromatography Experiment Chromatography experiment

Chromatography Experiment Chromatography experiment

Identifying Dyes in a Mixture Identifying dyes in a mixture Dots of single dyes

Identifying Dyes in a Mixture Identifying dyes in a mixture Dots of single dyes are placed alongside a dot of unknown mixture. The solvent travels up the paper, and then the pattern of the dyes in the mixture can be compared with the single dyes.

Your Turn Identifying dyes in a mixture You have two investigations to carry out:

Your Turn Identifying dyes in a mixture You have two investigations to carry out: 1. Use the pens provided – separate individual dyes from the mixtures of dyes in each pen. Which contains the most individual dyes? 2. Using the food dyes – compare the individual dyes making up each food colouring. Which is the purest food colouring (e. g. has the least number of dyes)?

Uses of Chromatography Uses of chromatography How many uses of chromatography can you spot?

Uses of Chromatography Uses of chromatography How many uses of chromatography can you spot?

Which separation technique?

Which separation technique?

Separating Mixtures Separating mixtures

Separating Mixtures Separating mixtures

Anagrams

Anagrams

Chromatography Quiz Multiple-choice quiz

Chromatography Quiz Multiple-choice quiz

Separating mixtures Cut out and stick the correct picture with it’s name and what

Separating mixtures Cut out and stick the correct picture with it’s name and what it separates into your book Chromatography Separates liquids with different boiling points Distillation Separates a liquid and solid by boiling off the liquid Filtration Separates liquids of different colours Evaporation Separates a solid that can dissolve from one that can’t