Karteikarten
Equilibria
Karten in diesem Stapel (33)
- 1What systen is an equilibrium established inClosed system
- 2What does equilibrium reachNatural balance between products and reactants
- 3Why is chemical equilibria dynamicForward and reverse reactions continue to occur
- 4What does the rate of the forward reaction equal to in equilibriaRate of the reverse reaction
- 5What happens to the concentrations at equilibriumBoth remain constant unless conditions change
- 6What are the concentrations like if the equilibrium lies to the leftThe reactants concentration is higher than the products
(lines dont cross on graph) - 7What are concentrations like if the equilibrium lies to the rightProducts concentrations are higher than the reactants
(lines cross on graph) - 8What is Le Chateliers PrincipleIf a system in equilibrium is subjected to change, the position of equilibrium will move in the direction that opposes that change
- 9If the reactants are pink and the products blue, what is the colour at equilibriumPurple- mixture of pink and blue species
- 10When excess concentrations of a reactant is added what happes to equilibriumShifts right
Solution becomes colour of products - 11Why does increasing the concentration of reactants shift equilibrium to the rightOppose the change and reduce the concentration of the added reactant
- 12Why does increasing the concentration of the products shift equilibrium to the leftTo oppose the change and reduce the concentration of the added product
- 13What happens if silver nitrate is added to a reaction where Cl- is a reactantRemoves Cl- ions
Concentration of reactants decreases so the position of equilibrium will shift to the left to oppose the change and increase concentration of the reactants - 14What happens if there is a change in total pressure in equilibriumIncreased- equilibrium shifts to side with fewer moles of gas as fewer moles of gas exert less pressure
Decreased- shift to side with more moles of gas as more moles of gas exert more pressure - 15Why does equilibrium shift to the right if the total pressure is increasedFewer moles of gas on right
Shifts right to oppose the change and reduce the pressure, fewer moles exert less pressure - 16What does changing the temperature do to equilibriumIncreased- move in direction of endothermic reaction (+H)
Decreased- move in direction of exothermic reaction (-H) - 17If the forward reaction is exothermic what does increasing temperatures do to equilibriumShifts to left to oppose the change and absorb the heat
Increase yield of products- low temperatures required - 18What does temperature do to the forward and backwards reactions if increasedAlways increases the rate of both forward and backwards reactions but to different extents
- 19What effect does a catalyst have on equilibrium and yieldNo effect as it increases the rate of the forward and reverse reactions by the same amount
Catalysts always increase rate - 20Why is decreasing the temperature good and bad in Haber processGood- increases the yield of ammonia (yield of products)
Bad- Decreases the rate of reaction - 21What is the pressure of the haber process and why200 atm (atmospheres)
High enough for good yield and rate but high pressures require expensive equipment and can be safety risk - 22What is the temperature of the Haber process and why400-450 C
High enough for rate but still gives reasonable yield
A compromise - 23What catalyst does the Haber process use and whyIron- increases rate
- 24Why is the Haber process recycledReduces raw material and energy costs
- 25What is the equilibrium constant, KcEquilibrium constant in terms of concentrations of the reactants and products
- 26What is the Kc equation[C]c [D]d / [A]a [B]b
[Products]/ [Reactants] - 27What does it mean if the Kc value is significantly lower than 1Concentration of reactants are greater than products- equilibrium lies to the left
- 28What does it mean if the Kc value is significantly more than 1Concentration of products are greater than reactants- equilibrium lies to right
- 29What does the Kc units depend onThe amount of moles of each substance
(large number in front of symbol equation) - 30What effect does temperature have on KcIf temperature causes equilibrium to shift to the right, Kc will increase
If equilibrium shifts left, Kc decreases - 31What effect does a catalyst or change in concentration have on KcNo change
- 32what are the standard Kc unitsmol dm-3
- 33What happens to volume and units if the reaction has the same number of units on each side of the equilibriumVolume- cancels so moles can be used to calculate Kc
Units- cancel so Kc has no units
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- Beschreibung
- A level Chemistry Karteikarten am Equilibria, erstellt von Mistaya Illingworth-Rudd am 06/06/2024.
- Erstellt von
- Mistaya Illingworth-Rudd
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