W5 Jan S3 Pure Chem CNY 3 Separation Techniques 2

What are the correct sequence of steps to take in order to obtain a sample of ethanol from an ethanol - water mixture?

• Boil the mixture until fully evaporated and collect the residue.

• Boil the mixture and collect the vapour in a gas syringe.

• Boil the mixture, pass the vapour through a condenser and collect the condensed liquid.

• Boil the mixture, stir well and leave the mixture to settle.

In the following setup used to separate a miscible liquid-liquid mixture, which point contains the highest proportion of the liquid with a higher boiling point?

• A

• B

• C

• D

In the following set up, liquid compounds M (boiling point 68 ^oC) and N (boiling point 97 ^oC) react to form compound L (boiling point 50 ^oC). This reaction is a slow reaction. 

What is the purpose of the condenser in this set up?

• to allow liquid L to escape as fast as it is formed

• to enable M and N to mix more efficiently

• to keep air away from the reacting liquids

• to prevent M and N from escaping before the reaction is complete

Which of the following substances, when mixed with water can be separated using a separating funnel? Select all options that are correct.

• ethanol

• ink

• oil

• orange pulp

A student was given three different mixtures X, Y and Z to separate. 

X: ethanol and water

Y: petrol and water

Z: purple food dye and water

Which mixture(s) should be separated by simple distillation, fractional distillation, or the use of a separating funnel?

• A

• B

• C

• D

Which of the following Chinese New Year items did you see the most of this year?

Note: There is no correct answer for this question.

• 
• 
•