Chemistry 0620

1 In which changes do the particles move further apart? W X gas liquid solid Y Z A W and X B W and Z C X and Y D Y and Z

1 Which row describes the arrangement and movement of particles in a liquid? arrangement of particles movement of particles A touching and regular vibrating B touching and random moving around each other C touching and regular moving around each other D touching and random moving very fast

1 Iodine changes directly from a grey solid to a purple gas when it is heated. What is the name of this process? A condensation B evaporation C separation D sublimation

1 A 1 cm3 sample of substance X is taken. This is sample 1. X is then converted to a different physical state and a 1 cm3 sample is taken. This is sample 2. Sample 2 contains more particles in the 1 cm3 than sample 1. Which process caused this increase in the number of particles in 1 cm3? A boiling of liquid X B condensation of gaseous X C evaporation of liquid X D sublimation of solid X

1 Decane has a freezing point of –30 °C and a boiling point of 174 °C. A small sample of decane is placed in an open beaker in an oven at a temperature of 120 °C and at atmospheric pressure for 24 hours. What happens to the sample of decane? A It boils. B It evaporates. C It melts. D It sublimes.

1 Which row describes what happens to the particles in solid iodine when it is heated and turned into a gas? separation of particles speed of particles A closer together faster B closer together slower C further apart faster D further apart slower

1 The particles in a substance are far apart, randomly arranged and moving. The substance changes state and the particles are now close together. The particles are still randomly arranged and able to move. What is the change of state of the substance? A gas to liquid B liquid to gas C liquid to solid D solid to gas

2 Gases are separated from liquid air by fractional distillation. The boiling points of four gases are shown. Which gas is both monoatomic and a liquid at –200 C? gas boiling point / C A argon –186 B helium –269 C neon –246 D nitrogen –196

2 A mixture is separated using the apparatus shown. mixture funnel filter paper What is the mixture? A aqueous copper(II) sulfate and aqueous sodium chloride B aqueous copper(II) sulfate and copper C copper and sulfur D ethanol and ethanoic acid

2 Some sugar is contaminated with glass. How is a sample of solid sugar obtained from the mixture? A dissolve in water and then evaporate B dissolve in water, then filter and then dry the solid residue C dissolve in water, then filter and evaporate the filtrate D dissolve in water and then distil

2 Solid carbon dioxide changes directly into a gas under suitable conditions of temperature and pressure. Carbon dioxide gas moves from a high concentration to a low concentration. Which row names these two processes? changing from solid to gas moving from a high concentration to a low concentration A evaporation Brownian motion B evaporation diffusion C sublimation Brownian motion D sublimation diffusion

2 A student put exactly 25.00 cm3 of dilute hydrochloric acid into a conical flask. The student added 2.5 g of solid sodium carbonate and measured the change in temperature of the mixture. Which apparatus does the student need to use? A balance, measuring cylinder, thermometer B balance, pipette, stopwatch C balance, pipette, thermometer D burette, pipette, thermometer

2 A student put exactly 25.00 cm3 of dilute hydrochloric acid into a conical flask. The student added 2.5 g of solid sodium carbonate and measured the change in temperature of the mixture. Which apparatus does the student need to use? A balance, measuring cylinder, thermometer B balance, pipette, stopwatch C balance, pipette, thermometer D burette, pipette, thermometer

2 A student put exactly 25.00 cm3 of dilute hydrochloric acid into a conical flask. The student added 2.5 g of solid sodium carbonate and measured the change in temperature of the mixture. Which apparatus does the student need to use? A balance, measuring cylinder, thermometer B balance, pipette, stopwatch C balance, pipette, thermometer D burette, pipette, thermometer

© UCLES 2021 0620/12/F/M/21 3 Impurities change the melting and boiling points of substances. Sodium chloride is added to a sample of pure water. How does the addition of sodium chloride affect the melting point and the boiling point of the water? melting point boiling point A increases increases B decreases decreases C increases decreases D decreases increases

© UCLES 2021 0620/11/M/J/21 3 Which statement about paper chromatography is correct? A A solvent is needed to dissolve the paper. B Paper chromatography separates mixtures of solvents. C The solvent should cover the baseline. D The baseline should be drawn in pencil.

3 Which statement about paper chromatography is correct? A A solvent is needed to dissolve the paper. B Paper chromatography separates mixtures of solvents. C The solvent should cover the baseline. D The baseline should be drawn in pencil.

© UCLES 2021 0620/13/M/J/21 3 Which statement about paper chromatography is correct? A A solvent is needed to dissolve the paper. B Paper chromatography separates mixtures of solvents. C The solvent should cover the baseline. D The baseline should be drawn in pencil.

© UCLES 2021 0620/11/O/N/21 3 A student separates sugar from pieces of broken glass by dissolving the sugar in water and filtering off the broken glass. filtrate What is the filtrate? A broken glass only B broken glass and sugar solution C pure water D sugar solution

© UCLES 2021 0620/12/O/N/21 3 A student separates sugar from pieces of broken glass by dissolving the sugar in water and filtering off the broken glass. filtrate What is the filtrate? A broken glass only B broken glass and sugar solution C pure water D sugar solution