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AS/A-Level Chemistry - Calculations with Kc

Calculations with Kc

July 5, 2021

N2O4⇌ NO2 

N2O4 and NO2 are at equilibrium. The amounts present at equilibrium are 3.60g N2O4 and 14.70g NO2. The volume of the container is 200cm3

1 mol ethanoic acid was added to 0.5 moles of ethanol and was left to reach equilibrium. At equilibrium 0.58 mol of ethanoic acid was left.   

CH3COOH+ CH3CH2OH ⇌ CH3COOCH2CH3+ H2

In this instance, the “V”s cancel out and Kc can be derived from moles. 

1 mole of ethanoic acid was added to one mole of ethanol. If Kc = 4,  calculate the number of moles of ethyl ethanoate and equilibrium. 

CH3COOH+ CH3CH2OH ⇌ CH3COOCH2CH3+ H2

CH3COCH3+ HCN ⇌ CH3C(CN)(OH)CH3 

If Kc = 30 dm3mol-1 calculate the number of moles of HCN required to produce one mole of produce if you start with 4 moles of propane in 2 dm3 of ethanol (acting as asolvent). 

X = 1.022 mol of HCN 

Drafted by Eunice(Chemistry)