Chromatography and distillation

9.Why can't salt be removed from seawater by filtration?

10.In chromatography, what does it mean if two inks have a dye that travels the same distance?

11.What does the term 'soluble' mean?

12.What does the term 'solvent' mean?

13.A student performs chromatography on a mixture of three dyes using water as the solvent. After the experiment, the chromatogram shows three spots at different heights. Which conclusion is correct?

14.A mixture of two liquids, X and Y, is separated by simple distillation. The boiling point of X is 78°C and that of Y is 100°C. The distillate collected first is X. What is the most likely reason for this?

15.In a chromatography experiment, a red dye and a blue dye are separated. The red dye travels 4 cm and the blue dye travels 6 cm from the starting line. The solvent front is 10 cm. What is the Rf value of the blue dye?

16.In a simple distillation setup, a condenser is used. What is the main function of the condenser?

17.A student performs chromatography on a mixture of four dyes. The chromatogram shows four spots. Which statement about the dyes is correct?

18.A mixture of ethanol (boiling point 78°C) and water (boiling point 100°C) is distilled. Which substance is collected first and why?

19.In the chromatography diagram from the source, which two inks share a common dye?

20.A student wants to obtain pure water from seawater. Which method should they use?

21.In a chromatography experiment, a spot of ink is placed on the baseline and the solvent is allowed to run. After drying, the chromatogram shows two spots: one at 2.5 cm and one at 5.0 cm from the baseline. The solvent front is 10.0 cm. What is the Rf value of the slower-moving dye?

22.A student claims that salt can be removed from seawater by filtration. Why is this incorrect?

23.What is the state change called when a gas turns into a liquid?

24.In simple distillation, what is the purpose of the cooling water in the condenser?

25.In the chromatography diagram from the source, the orange ink and the purple ink both have one dye in common. How can this be determined?

26.In a chromatography experiment, a spot of ink is placed on the baseline and the solvent is allowed to run. After drying, the chromatogram shows two spots: one at 2 cm and one at 5 cm from the baseline. The solvent front travelled 10 cm. What is the Rf value of the faster-moving dye?

27.A student performs chromatography on a mixture of three dyes using water as the solvent. After the experiment, the chromatogram shows three spots at different heights. Which statement about the dyes is correct?

28.A mixture of two liquids, X and Y, is separated by simple distillation. The boiling point of X is 78°C and that of Y is 100°C. The distillate collected first is:

29.What is the state change called when a liquid turns into a gas?

30.In chromatography, what is the role of the paper?

31.Which statement about simple distillation is correct?

32.What is the name of the process when a liquid turns into a gas?

33.In the chromatography diagram from the source, how can you tell that two inks share a common dye?

34.A student performs simple distillation on a mixture of ethanol (boiling point 78°C) and water (boiling point 100°C). Which substance is collected first?

35.In a chromatography experiment, the solvent front travels 10 cm and a dye spot travels 6 cm from the baseline. What is the Rf value of that dye?

36.In simple distillation, what is the purpose of the condenser?

37.A chromatogram shows four spots from a mixture. Two spots have the same Rf value. What does this indicate?

38.In the chromatography diagram from the source, which two inks do NOT share a common dye?

39.In a chromatography experiment, a solvent front travels 12 cm and a dye spot travels 7.2 cm from the baseline. What is the Rf value of that dye?

40.A student performs chromatography on a mixture of three dyes using water as the solvent. After the experiment, the chromatogram shows three spots at different heights. The student measures the distance from the baseline to each spot: spot A = 2.0 cm, spot B = 5.0 cm, spot C = 8.0 cm. The solvent front travelled 10.0 cm. Which spot is the most soluble in water?