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A level Chemistry Equilibrium Question

H2O (g) + C (s) = H2 (g) + CO (g); ΔH = +131 kJ mol^-1*

When steam was passed over coke at 730°C, the following partial pressures were measured at equilibrium:*

p(H2O) = 90 kPa*
p(H2) = 183 kPa*

State what the equilibrium partial pressure of carbon monoxide is and hence calculate the equilibrium constant.*

Is the equilibrium partial pressure of CO 183 kPa?
What about the equilibrium constant, is it 372.1 kPa?

If the partial pressure of steam is increased to 150 kPa, what will be the new equilibrium partial pressure of hydrogen?
Original post by mocha520
H2O (g) + C (s) = H2 (g) + CO (g); ΔH = +131 kJ mol^-1*

When steam was passed over coke at 730°C, the following partial pressures were measured at equilibrium:*

p(H2O) = 90 kPa*
p(H2) = 183 kPa*

State what the equilibrium partial pressure of carbon monoxide is and hence calculate the equilibrium constant.*

Is the equilibrium partial pressure of CO 183 kPa?
What about the equilibrium constant, is it 372.1 kPa?

If the partial pressure of steam is increased to 150 kPa, what will be the new equilibrium partial pressure of hydrogen?

If there is neither of the products present intially, then the ratio of moles of each product formed is given by the coefficients of the balanced equation
Reply 2
Ya i know this so it means my answer is correct? As the number of mole of carbon monoxide should be the same as the number of mole of hydrogen so their partial pressure will be the same?

Original post by charco
If there is neither of the products present intially, then the ratio of moles of each product formed is given by the coefficients of the balanced equation
Original post by mocha520
Ya i know this so it means my answer is correct? As the number of mole of carbon monoxide should be the same as the number of mole of hydrogen so their partial pressure will be the same?


yes :smile:
Reply 4
then what if the partial pressure of steam is increased to 150 kPa, what will be the new equilibrium partial pressure of hydrogen
Original post by charco
yes :smile:
Original post by mocha520
then what if the partial pressure of steam is increased to 150 kPa, what will be the new equilibrium partial pressure of hydrogen


Use the equilibrium constant that you calculated in the first part and the fact that pp(CO) = pp(H2)

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