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Physical chemistry
Amount of substance
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Cards (8)
number of particles = number of moles x avagadros constant
pV=nRT
p = pressure (Pa)
V = volume (m3)
n = moles
R = 8.31 jk-1mol-1
T = temperature (K)
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percentage\ yield\ =
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\frac{actual\ yield}{theoretical\ yield}\times100
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why is actual yield lower than theoretical yield?
• not all reactants react fully
• chemicals can be lost by being left in containers
What is percentage yield?
It’s a measure of the efficiency of a reaction. It shows how wasteful a process is
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\%\ atom\ economy\ =
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\ \frac{Mr\ of\ desired\ products}{sum\ of\ Mr\ of\ all\ reactats\ }\ \times100
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Benefits of a high atom economy
• better for environment as theres less waste
• more sustainable
• less expensive
What is atom economy
It’s how much of the reactants become the desired product.
