chapter 1 - experimental techniques Flashcards
properties of ammonia gas
less dense, very soluble, alkaline
properties of carbon dioxide
denser, slightly soluble, acidic
properties of sulfur dioxide
denser, very soluble, acidic
properties of chlorine
denser, soluble, acidicpr
properties of hydrogen chloride
denser, very soluble, acidic
properties of oxygen
denser, slightly soluble, neutral
properties of hydrogen
less dense, insoluble, neutral
properties of nitrogen
less dense, insoluble, neutral
methods of gas collection
downward displacement : gases that are denser than air
upward displacement : gases that are less dense than air
water displacement : gases that are insoluble or slightly soluble in water
drying agents of gases
concentrated sulfuric acid : all except for alkaline
quicklime (calcium oxide) : must be heated before use, all except acidic gases
fused calcium chloride : must be heated before use, all except ammonia
crystallisation process
heat solution in an evaporating dish to evaporate most of the liquid until a saturated solution is formed. stop heating before all the solvent has evaporated. cool the solution until crystals appear within the solution. filter the solution to obtain the crystals as residue. wash the crystals with cold distilled water to remove impurties and dry between pieces of filter paper
purpose of boiling chips in simple distillation
to ensure smooth boiling
condenser
water out on top, water in from bottom to ensure an efficient cooling system
purpose of thermometer in simple distillation
measures the temperature of vapour that is entering the condenser, so that the boiling point of the liquid can be measured.
fractionating column
contains glass beads that provides a surface for vapour to condense on
