organic Flashcards
(19 cards)
What is the result of fractional distillation of a mixture of two liquids in equal proportions?
The liquid with the higher boiling point will be present in greater proportion when the thermometer shows a steady reading.
Which method could be used to separate the products of the reaction between aqueous lead(II) nitrate and aqueous potassium iodide?
B crystallisation
For separation of substances using chromatography, what must the mixture be?
B be soluble in the liquid.
Which method is best for obtaining pure water from ink?
B distillation
Which test indicates that a sample of water is pure?
D When it evaporates, it leaves no residue.
What is the purpose of the condenser in the oxidation of ethanol to ethanoic acid?
C to prevent the ethanoic acid changing back to ethanol
In a distillation setup, where is the highest proportion of the liquid with the higher boiling point found when the thermometer first shows a steady reading?
At the position corresponding to the higher boiling point.
What is the total number of different dyes present in five inks if the chromatogram shows distinct spots?
(b) 4
What error is made if the thermometer is incorrectly positioned in a fractional distillation setup?
(a) The thermometer is in the wrong position.
What is the first step in the process of chromatography?
Spotting the mixture onto chromatography paper.
What does the kinetic particle theory explain regarding the spreading of bromine in a sealed flask?
The molecules move freely and spread out over time.
What name is given to the experiment used to identify components of mixtures?
Chromatography
What is required to change non-coloured substances into coloured spots in chromatography?
A locating agent.
What is the Rf value of a substance in chromatography?
The ratio of the distance travelled by the substance to the distance travelled by the solvent front.
What does the apparatus A in a distillation setup typically represent?
A distillation flask.
Why is an electric heater preferred over a flame in a distillation setup?
To provide a controlled and even heat source.
Fill in the blank: A mixture of two substances must be placed so that the spot is just below the level of the _______.
liquid
Which statement regarding ink mixtures is correct?
D Yellow ink may be present in green ink.
What is the correct order of processes used to separate copper(II) sulfate crystals from sand?
Filtration, crystallisation, drying.
