s3 chem Flashcards
(85 cards)
what is the Si Unit of time?
second (s)
what is the Si Unit of temperature?
kelvin (K)
temperature in K (kelvin) = temperature in degree celcius + ?
273
what is the Si Unit of length?
metre (m)
what is the Si Unit of mass?
kilogram (kg)
what is the Si Unit of volume?
cubic metre (m^3)
1m = ?dm
10
1m^3 = ?dm^3
? = 1000
what is the degree of accuracy of a pipette?
10.0 cm ^3 or 25.0cm^3 (e.g : 10, 20, 30)
what is the degree of accuracy of a volumetric flask?
100 cm^3 or 250cm^3
what is the degree of accuracy of a measuring cylinder?
a range of volumes to the nearest 0.5cm^3 (e.g: 31.5 cm^3 or 23.0 cm^3)
what is the degree of accuracy of a burette?
a range of volumes to the nearest 0.05 cm^3. (e.g: 31.55 cm^3 or 23.00 cm^3)
what kind of apparatus can we use to measure the volume of a gas?
gas sringe
what can a magnet be used to separate in the separation of solid-solid mixtures?
a magnet can be used to separate magnetic solids from non-magnetic solids
name 3 different ways/techniques to separate solid-solid mixtures.
magnetic attraction, sieving, and suitable solvents.
how does sieving work?
in a mixture of bigger and smaller particles, we can use a sieve of the right pore size to separate the components. The pore size tells us how big the holes in the filter are. Bigger pores let bigger particles through.
- a sieve can be used to separate solids with different particle sizes
how does using suitable solvents to separate solid-solid mixtures?
a suitable solvent can be used to separate solid-solid mixtures in which only one of the solids is soluble in the solvent.
name 4 different ways/techniques to separate solid-liquid mixtures
filtration, evaporation to dryness, crystallisation, simple distillation
what is evaporation to dryness used for?
to separate a dissolved solid from its solvent by heating the mixture until all the solvent has vaporised.
what is crystallisation used for?
to obtain a pure solid from its saturated solution. (saturated solution = one in which no more solute can be dissolved.
what is simple distillation used for?
to separate a pure solvent (liquid) from a solution.
what are 2 ways/techniques to separate liquid-liquid mixtures?
chromatography, fractional distillation
what is chromatography used for?
to separate a mixture of substances which have different solubilities in a given solvent.
what is fractional distillation used for?
to separate miscible liquids with different boiling points