Alt to prac
No description yet. This curated deck is ready for daily study.
Card preview (24)
what type of indicator to use in titration
methyl orange, phenophalein (only one end point)
why do we not use universal indicator in titration
has a range of colours (no set end point)
how and why do we heat alcohols
with a naked flame, in a water bath. naked flame because alcohols are extremely volatile
describe the experiment to reduce copper (III) oxide to copper
powdered solid and add heat and attach bung and delivery tube to provide dry hydrogen to the powedered solid.
how to test for products of combustion
burning material, filter funnel above flame, attach filter funnel to bung attached to delivery tube of limewater, and then another delivery tube to anhydrous copper sulfate (tests for CO2 and water)
how to test for rust
test tube 1 = air and oxygen test tube 2 = oil and boiled water (no air) test tube 3 = calcim chloride (no water)
what factors affect rate of reaction
• different temperature acid • different sizes of reactants/particles • concentration of acid
how to measure timing when insoluble thing is forming
• measure how long it takes for cross to disappear • change temp/conc of acid
constant variables in acid reaction
• cross • diameter of beaker • volume
what to do if there are large lumps
use pestle and mortar to crush
what physical things should you mention
• apparatus • exact volume/mass • chemical/substance
what you could possible do to get more marks
labelled diagram
what you should do when saying what you’re doing
state what experiment you will carry out
what is the principle of chromatography
difference in solubility that seperates different substances
what is stationary phase
the one which does not move with the sample
what is the mobile phase
one which moves with the sample
what does Rf mean
retention factor
how to figure out the Rf value?
distance moved by solute/distance moved by solvent
how to make colourless substances visible during chromatography
• dry chromatogram in oven • spray with locating agent • heat for 10 minutes in the oven
what is the water level
mobile phase
what is the chromatography paper
stationary phase
why do we draw line in pencil during chromatography
it is insoluble
how to do filtration
• mixture goes in a funnel with filter paper into a flask • residue is insoluble, filtrate goes through
how to do crystallization
• some water in solution is evaporated (solution becomes more concentrated • solution left to cool and crystallise (solubility decreases as temperateure decreases) • crystals are filtered to remove solvent