2.3 Optimising Production Flashcards
(16 cards)
3 factors that affect equilibrium (and therefore yield)
Concentration, pressure, temperature
5 factors that affect RoR (and therefore time)
Concentration, pressure, temperature, surface area, and presence of a catalyst
Raw material
Substances that are added into the reaction pathway which are converted into useful products.
By-product
Products that are not the main products of the chemical conversion, but are reused in the chemical pathway, are collected and used for another purpose, or have commercial value.
Waste product
Products that have no commercial value or use, so are disposed of.
Yield
Quantity of product formed through a process. Related to efficiency of reaction.
Percentage yield
Percent ratio of actual yield : theoretical yield
% yield = AY/TY x 100%
Advantages of higher temperatures to industry
Increased rate of reaction; therefore, saves time and boosts production.
Disadvantages of higher temperatures to industry
For reversible reactions, will lead to favouring of backward reaction, reducing yield.
More energy-intensive, leading to additional fuel costs, and burning fossil fuels and releasing greenhouse gases.
Advantages of increased pressure to industry
Increased rate of reaction; therefore, saves time and boosts production.
For reversible reactions, equilibrium will shift to favour side with fewer gas molecules, potentially increasing yield.
Disadvantages of increased pressure to industry
Reaction vessels necessary for high pressures are often costly.
More energy-intensive, leading to additional fuel costs, and burning fossil fuels and releasing greenhouse gases.
Compromise for temperature
Moderate temperature (~450 degrees Celsius)
Compromise for pressure
Atmospheric pressure (1 atm)
Effect of using catalyst on manufacturer
Catalysts lower activation energy, so reactions occur faster at lower temperatures and pressures.
So, faster production, reduced costs (e.g. energy bills, workers’ wages), higher efficiency.
Effect of using catalyst on environment
Reduced energy consumption, as activation energy is lowered. So, less greenhouse gas emissions due to reduced fossil fuel consumption.
Reduced waste, as catalysts are not consumed in reaction and are often reused for many cycles.
Reduced use of non-renewable raw materials.
Industrial benefit of high reaction rate (with respect to profit)
Products are produced in minimum time. So, profits are increased, as products are available for consumers sooner, and less money is spent on wages for workers.
