Open Book Sep Techs 2018tes
Open Book Sep Techs 2018tes
Open Book Sep Techs 2018tes
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5. Decanting separates two ___________ with different densities or a solid from a _______(2)
6. Which two processes would you use to separate a mixture of sand, salt, and water?
7. Why is it not possible to separate salt from sea water by filtration? ____________________
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8. Complete the following table based on your knowledge of mixture separation techniques. (4)
Separates liquids
Evaporation
with different boiling
points
(i) What substance is given off when salt solution is heated gently? (1)
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(ii) What is the name of the process taking place in the beaker? (1)
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(iii) What will be left in the dish when heating is finished? (1)
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(iv) How can we obtain a salt solution from what is left in the beaker? (1)
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2. The following figure shows the process of distillation. Observe the given figure and answer
the questions that follow.
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(i) How can we predict which substance will change into vapours first? (2)
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(iii) Write two ways in which this process is helpful in our daily lives. (2)
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3. Chromatography is used to separate substances of different mass and is a separation
technique used extensively in forensic science to assist in solving crimes. The chromatogram
below shows 6 substances which have been separated using stand up chromatography. Use this
chromatogram to answer the questions below
X X X X X X X
A B C D E F Y
(i) Study the chromatogram and match the dots on Y to the other dots, and then work out
what substance Y is made of. What is substance Y? (2)
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(ii) Which other solvent could you use if the inks are insoluble in water?(1) _______________
(iii) Explain how you would obtain a similar chromatogram? You should use a labelled
diagram to help with your explanation. (6)