chem paper 2 - more worst topics Flashcards
(28 cards)
what is reacted with ethanol to produce ethanoic acid
oxidising agent
what instrumental method could be used to show the presence of metal ions or the conc of metal ions in dilute solutions
whats 3 pros of using it than a chemical test
flame emission spectroscopy
more accurate, more sensitive, faster
why does the increase in the worlds population cause an increase in the conc of methane in the atmosphere
increased population so more waste produced which produces more methane on decomposition
explain why the Rf values for red dye might be different when using 2 different types of chromatography paper e.g. paper A and paper B (3)
Rf value is smaller for paper A
since the red dye is more attracted to paper A
so red dye spends a greater amount of time distributed in paper A than B
what is bioleaching
using bacteria to produce leachate solutions (that contain metal / copper compounds)
what are two solvents that can be used for chromatography
water and ethanol
explain how a manganese dioxide catalyst increases the rate of decomposition of hydrogen peroxide (2)
catalyst provides a different pathway for the reaction
this pathway has a lower activation energy
what is the gerneral name for a material that consists of wood particle reinforcements embedded in a poly(ethene matrix)
composites
what is the general name given for the 4 different monomers that make up a double helix
nucleotides
why do the concs of the substances do not change at dynamic equilibrium
because the forward and reverse reactions are taking place at the exact same rate
what are the 4 factors that increase the rate that a reaction happens
increasing the temp, increasing conc, increasing pressure, increasing surface area, adding a catalyst
how does increasing surface area increase the rate of reaction (3)
- it inceases the collision frequency, this increases the rate of reaction
- often done by breaking up a solid into smaller lumps like powder
- increasing the surface area to volume ratio making sure more particles are exposed to attack
how does increasing temp (4)
- it increases the energy of reactant particles
- meaning a greater proportion of particles will have the more energy than the activation energy that is needed
- so they will collide more frequently with a higher amount successful collisions
- increasing the rate of reaction
how does increasing conc and pressure increase the rate of reaction (2)
it increases the collision frequency frequency, which increases the rate of reaction
pros (2) and cons (1) of using a catalyst
pro - its expensive but cost effective as they increase rate of reaction and cheaper paying for it up front than paying for energy to increase the temp or pressure
pro - reducing necessary temp and pressure so less fossil fuels need to be burnt
con - many are toxic and could contaminate the ecosystem
descibe exothermic and endothermic reactions
exo - transfer energy from reactants to surroundings
endo - transfer energy from surroundings to reactants
reacting an alkene with hydrogen gas and a catalyst produces what
an alkane
reacting an alkene with water (at a high temp and a catalyst) produces what
what is it’s functional group name
an alcohol (OH)
reacting an alkene with a halogen produces what
a halogenoalkane
are alkenes saturated or unsaturated
unsaturated
for an addition reaction what else does there need to be
high pressure and a catalyst
what is the general formula for alcohols
Cn H2n+1 OH
what are the 3 similar properties of alcohols (well the first 4 alcohols)
what is the general equation for its first property
flammable (Cn H2n+1 OH + 02 -> CO2 + H2O)
soluble
can be oxidised to form carboxylic acids
what is the functional group for a carboxylic acid
- COOH
