Maxwell-Boltzmann Kinetics

A catalyst always...

• Creates more intermediates in a reaction mechanism.

• Increases the rate of a chemical reaction.

• Results in fewer elementary steps and therefore proceeds at a faster rate.

• Increases the activation energy.

Answer explanation

The use of a catalyst results in a faster reaction rate by providing the reaction an alternative pathway with a LOWER activation energy.

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NGSS.HS-PS1-5

Which of the following statements is TRUE regarding this Maxwell Boltzmann distribution curve?

• The activation energy is higher for temperature 1 than temperature 2.

• The reaction rate is higher for temperature 1.

• More molecules in temperature 1 have a greater average kinetic energy than seen in temperature 2.

• More molecules react in temperature 2 than in temperature 1.

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NGSS.HS-PS1-5

What is the rate law for this mechanism?

• rate = k[A][B]²

• rate = [B][X]

• rate = [A]^0.5[B]^1.5

• rate = [W][Y][Z]

Tags

NGSS.HS-PS1-5

Given the reaction mechanism below:

1. B₂ + 2A --> A₂B + B⁺ (slow)

2. A₂B + C --> A₂ + CB (fast)

Which of the following rate laws agree with the proposed reaction mechanism?

• Rate=k[B]²[A₂]

• Rate=k[A]²[B₂]

• Rate=k[B₂][A]²[C]

• Rate=k[A₂B][C]

Tags

NGSS.HS-PS1-5

2X₂ + 2BY --> 2X₂Y + 2B

The reaction shown above has the rate law expression

Rate=k[X]²

Which of the following will increase the rate of the chemical reaction?

• Adding a catalyst

• Lowering the temperature of the reaction

• Decreasing the pressure

• Increasing the concentration of X₂

Tags

NGSS.HS-PS1-5

For the reaction shown below, the rate of disappearance of O₂ is 8.6 x 10^-9 M/s . At what rate will [CO₂] change over the same time period?

CH₄ + 2O₂ --> CO₂ + 2H₂O

• (8.6x10^-9M/s)(2/1)

• (8.6x10^-9M/s)

• (8.6x10^-9M/s)(1/2)

• (8.6x10^-9M/s)(2/2)

Tags

NGSS.HS-PS1-7

For a certain chemical reaction, the order with respect to the reactant CH₄ is first order. How would the rate change if the concentration of CH₄ is quadrupled?

• The rate would increase by a factor of 4

• The rate would increase by a factor of 2

• The rate would increase by a factor of 1

• The rate would remained unchanged.

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NGSS.HS-PS1-5

Why does a higher temperature increase the rate of a reaction?

• it increases both the frequency and energy of particle collisions

• it only increases the frequency of particle collisions

• it only increases the energy of particle collisions

• it reduces the activation energy of the reaction

Tags

NGSS.HS-PS1-5

The above reaction will experience a rate decrease by the removal of a catalyst. Which of the following best explains why?

• Catalyst increase the required activation energy.

• Catalyst increases the temperature of the reaction.

• Catalyst lowers the temperature of the reaction.

• Catalyst lower the required activation energy.

Given the following balanced equation : 2NO(g) + Cl₂(g) → 2NOCl(g) If the rate of disappearance of Cl₂ is 4.84 x 10^-2 Ms^-1, what is the rate of disappearance of NO?

• 1.45 x 10^-2 Ms^-1

• 2.42 x 10^-2 Ms^-1

• 3.67 x 10^-2 Ms^-1

• 9.68 x 10^-2 Ms^-1

Tags

NGSS.HS-PS1-5