Unit 3: Chemistry in Society Flashcards
Why is a high yield important in industry?
In order to maximise profits
What is a feedstock?
a reactant from which other chemicals can be extracted or synthesised.
Where do feedstocks come from?
Raw materials such as crude oil, air and water.
How can we calculate the mass of a substance?
Multiply the GFM with the number of moles
How can we calculate the number of moles of a substance?
Either multiply the concentration by the volume, or divide the mass by the GFM
How can we calculate the volume of a substance?
Either multiply the number of moles with the molar volume or divide the number of moles by the concentration
How do we calculate the percentage yield?
Actual Yield divided by Theoretical Yield (x100)
What are the 5 reasons why the yield will not likely be 100%?
- Unreacted Reactants
- Side reactions occuring
- Purification (leading to loss of product)
- Human error
How can we calculate the atom economy?
Mass of desired product divided by the total mass of reactants (x100)
What is equilibrium?
When the rate of the forward reaction is equal to that of the reverse reaction
An increase in concentration for the products will do what?
Speed up the forward reaction
In a reversible reaction, if the forward reaction is exothermic then what will the reverse reaction be?
Endothermic
Which reaction will a fall in temperature favour?
exothermic reaction
Which reaction will a rise in temperature favour?
endothermic reaction
In a reversible reaction, an increase in pressure will do what to the equilbrium?
It will cause it to shift in the direction which results in a decrease in the number of gaseous molecules
