Getting the Most from Reactants Flashcards
factors to consider making a new product
- availability, sustainability, and cost of feedstock(s)
- opportunities for recycling
- energy requirements
- use of by-products
- yield of product
availability, sustainability, and cost of feedstock(s) - profit making and profit losing
making - a locally sourced feedstock would be ideal to maximise profits
losing - transportation of feedstock may have cost, safety, and environmental implications
- finite resources may be more costly and have to be bought upfront
- the cost of energy from fossil fuels can often fluctuate
opportunities for recycling - profit making and profit losing
making - unreacted materials can be fed back into the reactor to improve efficiency and profitability of the process and reduce waste
losing - unreacted materials which are difficult to separate from the products can make reactions inefficient and wasteful
energy requirements - profit making and profit losing
making - exothermic reactions can be used to provide heat, saving on energy bills
- catalysts can be used to allow reactions to take place at lower temperatures
losing - reactions that require heating or indeed cooling are often costly
use of by-products - profit making and profit losing
making - many reactions produce more than one product, if this can be used elsewhere or sold this saves money
losing - by-products which are toxic or environmentally damaging can be expensive to deal with
yield of product - profit making and profit losing
making - a high yield is very profitable
losing - low yield is costly in terms of money and time
what is a raw material
useful substances which are found naturally e.g crude oil, water, metallic ores
what is a feedstock
a substance that is derived from a raw material that is used to manufacture another substance
what does excess mean
having too much of something
what is the limiting reagent
usually, one a reactant runs out before the other and this reactant limits how much product can be formed
what type of reactant should be used when calculating the mass of a product
the limiting reagent
what is the molar volume
the volume taken up by 1 mole of a gas
what is the percentage yield
a measure of how much of a product is obtained compared to the amount expected if there was complete conversion
percentage yield equation
% yield = actual yield
———————— x 100
theoretical yield
what is atom economy
measures the proportion of the total mass of all starting materials successfully converted into the desired product
