2019 paper 2 Flashcards
why is bitumen not used as a fuel (it has a high boiling point)
its a longer hydrocarbon so it’s not very flammable
its too viscous
explain why large hydrocarbons are cracked to make smaller ones
Beacuse smaller hydrocarbons make better fuels and are have greater demand and larger hydrocarbons are too viscous
how to go from mg to g
x 10^-3
what equipment would you need to find the rate of production of hydrogen gas
gas syringe
stopwatch
how to work out rate of reaction
volume produced/ time
why doesn’t stainless steel rust
because it contains alloys of chromium and nickel and is resistant to corrosion
what do you need in order for iron to rust
BOTH water and oxygen
why does an aluminum coating stop iron from rusting
aluminum is more reactive than iron so it provides sacrificial protection as it corrodes before iron
why is burning woods better than burning oil
wood is renkneweable
wood is carbon neutral - doesnt add to global warming
why does a thermosoftening polymer melt
contains no cross links and weak intermolecular forces
a composite material containing glass fibers surrounded by polyester. wich is the matrix and wich is the reinforcement
matrix is the binder
matrix - is polyester
reinforment - glass fibres
how to test a water sample for sulfate ions
add barium chloride
add dilute hydrochloric acid
a white precipitate will form
plan an investigation to find total mass of dissolved solids in 100cm^3 of drinking water
weigh empty evaporating basin
add a set volume of water
weigh basin and water
heat using bunsen burner
reweigh
repeat heating until constant mass obtained
subtract mass of mass of basin from mass
is an alkane or alkene unsaturated
alkene ( double bond is unsaturated)
how to find out if aliminium is in a substnce
add sodium hydroxide
white precipitate
aluminum dissolves in excess sodium hydroxide
