KInetics

Question 1

Define activation energy

Answer 1

The minimum energy which paricles need to collide to start a reaction

Question 2

Draw and label a maxwell distribution curve, Note important things about the drawing (mean, EMP, Origin and X axis)

Answer 2

The enerfy distribution should never meet x axis as there is no maximum energy for molecules
Always go through origin as there are no molecules with no energy
EMP is the most probable energy
Mean is not at the peak of the curve
Area under the curve represents the total number of particles present

Question 3

How can a reaction go to completion if few particles have greater energy than Ea

Answer 3

Particles gain energy through collisions

Question 4

Explain the effect of increasing temp on the maxwell boltezman curve

Answer 4

Curve is less steep and apears wider but the total area under the curve should remain constant

Question 5

Explain the effect of increasing pressure and conc on maxwell boltzman curve

Answer 5

New curve will be higher and not cross over but same start from origin this is because Area under the curve will be greater as there will be more particles

Question 6

Describe the effect of pressure on heterogynous catalysts

Answer 6

Has limited effect as the reaction takes place on the surface of the catalyst. The active sites of the catalyst surface are already saturated with molecules so increasing pressure wont have an effect

Question 7

How do industrially catalusts reduce costs

Answer 7

Speed up rate of reaction so lower temp used but have no effect on equilibrium

Question 8

Describe the environmenral benefits of catalysts

Answer 8

Catalysed reaction can occur at lower temp so less fuel needed and fewer emission fuels
Catalysed reaction enables use of alternative process with higher atom economy so fewer raw materials and waste products