Chemistry Paper 2 Flashcards
gradient = ?
change in up/change in across
one way to collect gas?
what are 2 errors?
using inverted measuring cylinder and a tube through it.
gas already being in the measuring cylinder. Gas lost before you get the bung on.
for rate of reaction, the higher the……
temperature the faster the rate of reaction will be. This is because the particles have more energy so they can move around faster leading to more frequent successful collisions.
Lump means…
Powder has…
less surface area so less space to react.
more surface are so the particles are available to react.
The larger the surface area…
the faster the rate of reaction this is because there are more particles available to react leading to more successful collisions.
High pressure and high concentration means…
there are more of them meaning they are more likely to collide and react.
the higher the pressure or concentration…
the faster the rate of reaction will be because of more particles in a fixed volume so there is a higher chance of a successful collision.
a catalyst…
lowers the activation energy.
crude oil is…
a mixture of different length hydrocarbons.
alkanes?
single bonds only.
CnH2n+2
cracking using…
heat and a catalyst.
test for alkenes?
bromine water goes from orange to colourless
Alkenes?
CnH2n
complete combustion?
hydrocarbon + oxygen ——> water + carbon dioxide
incomplete combustion?
hydrocarbon + oxygen ——-> water + carbon dioxide + carbon monoxide + carbon
pure substance is?
1 element or compound
mixture?
two or more different substances which are not chemically bonded
compound?
two or more elements that are chemically bonded
chromatography?
separating mixtures.
Rf=?
Rf = distance moved by spot / distance moved by solvent
Test for hydrogen
oxygen
CO2
Cl
H - lighted splint will make a squeaky pop.
O - glowing splint and it will reignite.
CO2 - bubbled through limewater, that will turn milky/cloudy white.
Chlorine - Damp litmus paper bleaches white.
atmosphere %?
78% nitrogen
21% oxygen
0.04% carbon dioxide
early atmosphere?
ammonia
methane
water vapour
carbon dioxide.
how did oceans form?
what happened to the CO2?
water in atmosphere rained to make oceans.
carbon dioxide dissolved in oceans, locked up in rocks, photosynthesis.
three main greenhouse gases?
CO2
water vapour
methane
carbon in the air?
smog, global dimming.
make potable water?
desalination
add chlorine and flouride.
bioleaching?
bacteria breaking down ores to produce an acidic solution containing copper ions (leachate). Use scrap iron to displace copper from leachate.
phytomining?
plants absorbing metal ions through their roots. then burned to produce ash containing the metal compounds, acid added to produce leachate, displace using scrap iron.
