IMAT 2O16 Question 46

A mixture of methanol and ethanoic acid is left until equilibrium is reached. The equation for this
reaction is given below.
The amount of CH3OH in this mixture at equilibrium can be increased by:
1 adding more water to the mixture
2 raising the temperature of the mixture
3 adding sodium hydroxide to the mixture
4 adding a catalyst to the mixture
2 and 4 only
1 and 2 only
1 and 3 only
1, 2 and 3 only
4 only
The compounds carbon dioxide (CO2), propane (C3H8) and ethanal (CH3CHO) all have
Mr = 44.
Which of the following lists correctly shows these compounds in the order that they become
gases as their temperature rises from –100°C at the same pressure?
A/ CO2, C3H8, CH3CHO
B/ CH3CHO, C3H8, CO2
C/ CO2, CH3CHO, C3H8
D/ 3H8, CO2, CH3CHO
E/ C3H8, CH3CHO, CO2

hi!
for the second question:
we know that CO2 already has weak forces (nonpolar too) and also a gas at normal temperature with a low boiling point, It will be the easiest to become a gas
comparing between propane and ethanal, ethanal has a double bond oxygen and carbon which means it is stronger than a normal alkane
(propane)
that is why CO2 is the easiest, then propane then ethanal
hope it helps

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Thank you that was helpfull !

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for the first question:
we want to know how to make the equilibrium shift to the left for this question.
1st, if we add more water we will have an increase in the products side so the system will shift to the reactants side to decrease it, increasing CH3OH
2nd by the information given for the enthalpy of the system, we know that the reaction is exothermic. if we increase the temperature of the system, it will try to decrease the heat by going backward, left, increasing CH3OH
3rd if we add NaOH to the solution, it will ionize and have lots of extra OH in the solution. the system will try to decrease the amount by using the OH which means going to the left and using OH to make CH3OH
4th, if we add a catalyst both the activation energies of forward and reverse reaction decrease causing no change in the concentrations. only change can be seen as a faster reaction
hope it helps!

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