WorksheetsElements, Compounds, Mixtures and Separating Techniques
Total questions: 20
Worksheet time: 11mins
A compound is a substance made up of ___________ different ________ which are chemically bonded together.
two or more
non-metals
elements
one or more
metals
Iron is an example of a(n) (a) .
Oxygen and Nitrogen are both examples of...?
compounds
elements
mixtures
none of the above
Mixtures can be easily separated.
False
True
Pure substances are made up of a single element or compound.
True
False
__________ is used to separate an insoluble solid from a liquid.
Crystallisation
Filtration
Chromatography
Distillation
Crystallisation separates a(n) ___________ from a solution.
insoluble solid
soluble solid
gas
Salt can be obtained from a saturated solution by (a) .
What would I use the above apparatus for?
Separating a soluble solid from a solution.
Separating a pure liquid from a solution.
Separating a mixture of sand and salt water.
What is labelled X in this experiment?
Evaporating basin
Solvent vapour
Solution
Bunsen burner
I want to find an Rf value. I would use the following experiment...
Distillation
Chromatography
Filtration
Crystallisation
Simple distillation can be used to obtain pure water from salt water.
True
False
Sometimes
Rf values can be obtained with the following information.
Distance moved by the solvent.
Width of the baseline.
Length of the chromatography paper.
Distance that the substance has moved.
Label number 1 in the above experiment.
Solvent front
Solvent
Baseline
In chromatography, it is important the the baseline is drawn in ______.
Sharpie
Pen
Pencil
None of the above
Why is a lid used in chromatography?
To protect the paper.
To stop the paper getting wet.
To stop the baseline from dissolving
To stop the paper drying out during the experiment.
In chromatography, the sample spots should be...
small and concentrated.
two spots very close together.
large and concentrated.
none of the above.
Select the correct equation to calculate Rf values.
(Distance travelled by solvent) ÷ (Distance travelled by sample)
(Distance travelled by sample) ÷ (Distance travelled by solvent)
In chromatography, water and ethanol are both examples of what?
Mobile phase
Solvent front
Stationary phase
Sample spots
Fractional (a) separates mixtures of liquids by boiling point.
