Pure substances, mixtures and separation

9.Which property is used to separate a mixture of iron filings and sulfur powder using a magnet?

10.Which of the following are separation techniques that rely on differences in boiling points? (Select all that apply)

11.A pure substance consists of only one type of particle.

12.Match each separation technique to the property it exploits.

13.Place the following steps in the correct order to separate a mixture of sand, salt, and water by filtration and evaporation.

14.Which of the following is an example of a pure substance?

15.A mixture of ethanol (boiling point 78°C) and water (boiling point 100°C) is heated. Which substance will evaporate first?

16.A student has a mixture of ethanol (boiling point 78°C) and butanol (boiling point 117°C). Which separation technique is most suitable to separate them?

17.Which of the following are examples of physical separation techniques? (Select all that apply)

18.A mixture of iron filings and sulfur powder can be separated by adding water and then filtering.

19.Place the following steps in the correct order to separate a mixture of salt, sand, and water by filtration and evaporation.

20.In paper chromatography, the stationary phase is:

21.A student performs a chromatography experiment with two dyes: dye X and dye Y. Dye X travels 4.2 cm and dye Y travels 6.8 cm. The solvent front travels 10.0 cm. Which statement is correct?

22.Which of the following separation techniques rely on differences in boiling points? (Select all that apply)

23.Filtration can be used to separate a dissolved solid from a liquid.

24.Which of the following are examples of pure substances? (Select all that apply)

25.Place the following steps in the correct order to separate a mixture of salt and sand: (a) evaporate the filtrate, (b) filter the mixture, (c) add water to dissolve the salt.

26.In paper chromatography, the stationary phase is the solvent.

27.Which separation technique would be best to separate a mixture of ethanol (boiling point 78°C) and water (boiling point 100°C)?

28.A student is given a mixture of sand, salt, and iron filings. Which separation technique should be used first to remove the iron filings?

29.Two liquids, A (boiling point 80°C) and B (boiling point 120°C), are mixed. Which separation technique is most suitable to obtain pure A?

30.In a chromatography experiment, a mixture of dyes is separated. The solvent front travels 10.0 cm. Dye X travels 4.0 cm, and dye Y travels 7.0 cm. Which dye has a higher affinity for the stationary phase?

31.A student has a mixture of salt and sand. She adds water, stirs, then filters the mixture. Which substance remains on the filter paper?

32.A student performs paper chromatography on a mixture of three dyes. The solvent front travels 10.0 cm. Dye A travels 2.0 cm, dye B travels 5.0 cm, and dye C travels 8.0 cm. Which dye has the highest affinity for the stationary phase?

33.A pure substance is made up of only one type of atom or molecule.

34.Which of the following is a mixture?

35.Filtration can separate a dissolved solid from a liquid.

36.In the particle model, which state of matter has particles that are closely packed and vibrate in fixed positions?

37.Match each separation technique with the property it exploits.

38.Decantation involves carefully pouring off a liquid from a solid or another liquid that has settled.

39.Place the following steps in the correct order to separate a mixture of sand and salt using water:

40.Chromatography can be used to separate mixtures of dissolved substances based on their different rates of movement through a medium.

41.Complete the sentence about the particle model.

42.Define the term 'solute'.

43.A solution contains 5 g of salt dissolved in 95 g of water. What is the mass of the solution?

44.A student performs paper chromatography on a mixture. The solvent front travels 12.0 cm. A blue spot travels 9.0 cm and a red spot travels 6.0 cm. What is the difference in Rf values between the blue and red spots?

45.What is the name of the substance that dissolves in a solvent to form a solution?

46.Complete the sentence about particle arrangement.

47.In a chromatography experiment, a dye travels 6.5 cm and the solvent front travels 10.0 cm. Calculate the Rf value of the dye. Give your answer to two decimal places.

48.Complete the sentence using the correct terms.

49.What is the name of the process used to separate a solid from a liquid by pouring off the liquid without disturbing the solid?

50.A student dissolves 10 g of salt in 90 g of water. What is the total mass of the solution in grams?

51.In a chromatography experiment, a dye travels 7.2 cm and the solvent front travels 12.0 cm. Calculate the Rf value of the dye. Give your answer to two decimal places.

52.Complete the sentence about separation techniques.

53.Explain why distillation is used to separate a mixture of ethanol and water, rather than filtration.

54.Explain why fractional distillation is used to separate crude oil into its components rather than simple distillation.

55.A solution contains 5 g of salt dissolved in 95 g of water. What is the mass of the solution?

56.A student performs paper chromatography on a mixture. The solvent front travels 12.0 cm. A blue spot travels 9.0 cm and a red spot travels 6.0 cm. What is the difference in Rf values between the blue and red spots?

57.In a chromatography experiment, a dye travels 6.5 cm and the solvent front travels 10.0 cm. Calculate the Rf value of the dye. Give your answer to two decimal places.

58.A student dissolves 10 g of salt in 90 g of water. What is the total mass of the solution in grams?

59.In a chromatography experiment, a dye travels 7.2 cm and the solvent front travels 12.0 cm. Calculate the Rf value of the dye. Give your answer to two decimal places.