The first-order surface reaction A(g) ⟹A(ads) ⟹B(g) has a rate of 1.8 ×10^-4 mol ·dm^-3 ·s^-1.

step 1 This question is a review of several concepts that were introduced in this chapter. The first is

The first-order surface reaction A(g) ⟹A(ads) ⟹B(g) has a...

The first-order surface reaction $$ \mathrm{A}(\mathrm{g}) \Longrightarrow \mathrm{A}(\mathrm{ads}) \Longrightarrow \mathrm{B}(\mathrm{g}) $$ has a rate of $1.8 \times 10^{-4} \mathrm{~mol} \cdot \mathrm{dm}^{-3} \cdot \mathrm{s}^{-1}$. The surface has a dimension of $1.00 \mathrm{~cm}$ by $3.50 \mathrm{~cm}$. Calculate the rate of reaction if the dimensions of the two sides of the surface were each doubled. [Assume that $\mathrm{A}(\mathrm{g})$ is in excess.]

The first-order surface reaction
$$
\mathrm{A}(\mathrm{g}) \Longrightarrow \mathrm{A}(\mathrm{ads}) \Longrightarrow \mathrm{B}(\mathrm{g})
$$
has a rate of $1.8 \times 10^{-4} \mathrm{~mol} \cdot \mathrm{dm}^{-3} \cdot \mathrm{s}^{-1}$. The surface has a dimension of $1.00 \mathrm{~cm}$ by $3.50 \mathrm{~cm}$. Calculate the rate of reaction if the dimensions of the two sides of the surface were each doubled. [Assume that $\mathrm{A}(\mathrm{g})$ is in excess.]

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

First Order Reaction Kinetics

A first order reaction is one in which the rate is directly proportional to the concentration (or available amount) of one reactant. In scenarios where one reactant is in excess, the reaction rate primarily depends on the other reactant, providing a straightforward relationship between the available reactive species and the rate at which it is converted.

Surface Area Dependence in Heterogeneous Reactions

In heterogeneous reactions that occur on a surface, such as adsorption followed by reaction, the overall rate is influenced by the available surface area. An increase in surface area allows for more reactive sites for the process, leading to a higher overall reaction rate, assuming all other factors remain constant.

Geometric Scaling and Dimensional Analysis

When the dimensions of a surface are scaled, the surface area increases by the square of the scaling factor. For example, doubling each linear dimension of a rectangular surface results in a fourfold increase in its area. This principle is critical in understanding how modifications to the geometry of a reactor or catalyst surface can proportionally affect the reaction rate.

Transcript

Please give Ace some feedback