Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

FlashCards > Chemistry Unit 3 AOS2 > Flashcards

Chemistry Unit 3 AOS2 Flashcards

(51 cards)

Start Studying
1
Q

collision theory chp4

A

the rate of chemical reaction in terms of collison between particles, particles must have successful collisions to break bonds within reactions to form new products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

3 conditions for successful collisions chp4

A
  • reactants must physically collide with each other
  • reactants must collide with sufficient energy to break bonds (activation energy)
    -reactants must collide at correct orientation for bonds to break

These conditions also affect reaction rates and yield reactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the 5 factors affecting rate of reaction chp4

A
  • increasing surface area of solids
  • increasing concentration of reactants in solution
  • increasing pressure of gaseous soultions
  • increasing temperature
  • adding a catalyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

increasing surface area allows more … chp4

A

particles to collide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

More collisions means more …chp4

A

means more succesful collisions and faster reaction rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what happens if you break a solid into smaller parts? chp4

A

it means more particles are present at the surface and could react (surface area increasing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

more reactant parties in same volume means more … chp4

A

collisions so more succesful collisions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

increasing the pressure increases the … chp4

A

rate of reaction because there are more gas particles colliding with each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

increasing pressure is the same as increasing … chp4

A

concentration due to the same mass in a smaller volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

as temperature increases the average speed of the particles … chp4

A

increase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

the energy of the succesful collisions is more likley to exceed … chp4

A

the activation energy (Ek > Ea)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

as temperature increases … chp4

A

the percentage of particles that contain enough energy to overcome the Ea will incease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

an increase of … can … the reaction rate chp4

A

10 degrees and double

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

catalysts provide … chp4

A

alternative reaction pathway with lower Ea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how do you measure reaction rates chp4

A
  • temperature
  • change in mass due to solid formation or gas evoloved
  • precipitate formation/colour change
  • volume of gas evolved
  • pH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

catalysts are not … in a reaction but just … up the reaction, it … activation energy barrier chp4

A

consumed, speed, lowers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

the percentage yield remains … chp4

A

unchanged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

name the types of catalysts chp4

A
  • homogeneous catalysts = same physical state as reactants and products (eg.
  • heterogeneous catalysts = different physical state as the reactants and products
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what process does heterogeneous catalyst prefer and why chp4

A

industrial processes because they are easier to reuse, and be used in high temp, and easily separated from products of a reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

haber process in heterogenous catalysis chp4

A

haber process creates ammonia by reacting N2 and H2 gases using a powdered iron catalyst which reduces the temp.

the gases absorb onto the iron surface and breaks the bond.

new bonds form to make NH3 ammonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is a irreversible reaction and example chp5

Study These Flashcards
A

reactions that occur in one way (with single arrow) and cannot be converted back to reactants for example (eg. combustion of fuels)

22
Q

what is a reversible reaction chp5

Study These Flashcards
A

reaction that occur both directions (with double arrow) and can be converted from products to reactants for example (haber process of ammonia)

23
Q

what is equilibrium chp5

Study These Flashcards
A

the rate of the forward reaction will eventully equal the rate of the reverse reaction

24
Q

what is rate of a reaction and what influences it chp5

Study These Flashcards
A

how much product is formed over a given period of time
-temp
-concentration
-pressure
-use of catalyst

25
what is extent of reaction chp5
the proportion of reactants that are converted into products (yield of a reaction)
26
what is yield of reaction chp5
amount of products formed at end of reaction (yield=extent)
27
what is the equilibrium constant chp5
K is the ratio of concentrations of products to reactants in a reaction the magnitude of K can be used to indicate the exent of reaction
28
equilibrium is described as a ... chp5
dynamic state in closed systems
29
during dynamic equilibrium ... chp5
- reaction is never complete - all substances present - bonds break between reactant and product
30
what does equilibrium law state chp5
Kc is the ratio of concentration of products to concentrations of reactant at equilibrium
31
what are the 3 characteristics of equilibrium constant chp5
- if equation is reverse of another the kc are the inverse of eachother - if reaction is doubled the kc is squared - if the cofficents are halved the value of kc is sqaure root of original value
32
what is Qc chp5
Qc is a contrast to Kc in which it can be used to describe the extent of reaction the expression for the ratios of concentration not at equilibrium (at any point of reaction)
33
what is Le Chateliers principle chp5
LCP is if a equilbrium system is subjected to a change the system will adjust itself to partially oppose the change. - the result of the change is a shift in the equilbrium -never goes back to the same position
34
the position of equilibrium can be changed by chp5
- adding/removing a product or reactant - changing pressure by changing volume (gases) - dilution (solutions) - changing temp
35
what are compromised conditions chp5
in order for companies to operate efficiently and ensuring hazards are minimized compromised conditions are put in place
36
for the haber processes what are the actual conditions to overcome conflict between rate and yield chp5
- high pressures of 100-250atm - moderate temps of 350-550 degrees - porous iron/iron oxide catalyst
37
how green is haber process ammonia is ... chp5
ammonia is - responsible for half of the global fertalizers production - N2 gas is sourced from atmosphere - H2 gas is sourced from SMR process which is responsible for 90% of CO2 emissions - H2 produced from SMR is 'grey hydrogen'
38
grey hydrogen ... chp5
is a process where natural gas is reacted with steam to produce H2 gas and CO2 as a by product
39
how to decarbonsise ammonia production chp5
electrolysis of water to produce green hydoren
40
the wide spread use of green hydrogen is vital for which goal of sustainable development goals chp5
goal 2: zero hunger
41
why is it vital for the zero hunger goal chp5
fertalizers produced from green ammonia are sustainable solution for feeding growing population
42
what are 2 techniques used in industrial equilbrium processes chp5
- use of catalyst: increase rate of reactionn - use of heat exchangers: recover wasted heat
43
what is electrolysis chp6
non spontaneous reaaction involving passage between electrical energy from power supply through conducting liquid
44
name differences between electrolytic cells and galvanic cells chp6
galvanic - produces electricity -spontaneous -chemical>electrical -anode is negative cathode positive -2beaker - does not require external voltage source electrolytic - consumes electricity -non spontaneous -electrical>chemical - anode is positive cathode negative -1beaker - requires external voltage source
45
features of electrolytic cell
- reactants will not DIRECTLY react - products formed must be kept SEPARATE (otherwise spontaneous reaction occurs) -screen mesh is used to keep the electrodes separate - electrolyte allows flow of ions completing internal circuit - external circuit is electron flow through wire from anode to cathode
46
what are the 3 commerical cells
1) molten electrolytes 2) aqueous electrolytes 3) electrolysis involving reactive electrodes
47
what is electrorefining
refers to process of using electrolysis to purify metal extracted from ore
48
what is anode mud
are impurities less reactive the copper, silver, gold or platinum are not oxidized and fall from anode creating anode mud
49
what is electroplating
refers to whena thin surface coating of metal can be applied over another surface eg. tin cans mainly made of steel, have a thin layer of tin placed over the surface of the steel as tin corrodes very slowly
50
electroplating in electrolytic cells
electroplating occurs in electrolysis the object to be played is connected to wire to negative terminal of power supply becoming negative electrode electrode of metal is connected to positive terminal of power supply becoming positive electrode power supply acts as 'electron pump'
51

FlashCards (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions