What is a typical rate constant for a diffusion-controlled reaction in aqueous solution?

(a) The mechanism of a reaction consists of a pre-equilibrium step with forward and reverse activation energies of $25\ \mathrm{kJ}\ \mathrm{mol}^{-1}$ and $38\ \mathrm{kJ}\ \mathrm{mol}^{-1},$ respectively, followed by a rate-limiting elementary step of activation energy $10\ \mathrm{kJ}\ \mathrm{mol}^{-1}.$ What is the activation energy of the overall reaction? (b) The mechanism of a reaction consists of a pre-equilibrium step with forward and reverse activation energies of $27\ \mathrm{kJ}\ \mathrm{mol}^{-1}$ and $35\ \mathrm{kJ}\ \mathrm{mol}^{-1},$ respectively, followed by a rate-limiting elementary step of activation energy $15\ \mathrm{kJ}\ \mathrm{mol}^{-1}.$ What is the activation energy of the overall reaction?

Suppose you moved 8 meters forward and then 3 meters backward. What is your displacement from your original position? A 5 m forward, B 8 m forward, C 11 m backward, D 24 m backward.

Given that the two key reactions for splicing could proceed in the forward or reverse direction, what prevents the splicing reactions from proceeding backward in vivo?

Is a system at equilibrium if the rate constants of the forward and reverse reactions

Assuming that the density remains unchanged, compare the specific strength of the 2090-T6 aluminum alloy to that of a die cast 443-F aluminum alloy. If you considered the actual density, do you think the difference between the specific strengths would increase or decrease? Explain.

For the aluminum alloy whose stress–strain behavior can be observed in the Tensile Tests module of VMSE, determine the following: (a) the approximate yield strength (0.002 strain offset) (b) the tensile strength (c) the approximate ductility, in percent elongation How do these values compare with those for the 2024 aluminum alloy (T351 temper).

How many pounds of a $12 \%$ aluminum alloy must be mixed with $400 \mathrm{~lb}$ of a $30 \%$ aluminum alloy to make a $20 \%$ aluminum alloy?

A sample of aluminum metal absorbs 9.86 J of heat, upon which the temperature of the sample increases from 23.2$\degree$C to 30.5$\degree$C. The specific heat capacity of aluminum is 0.90 J/g$\cdot$K. What is the mass of the sample?

A convenient source of gamma rays for radiation chemistry research is ${ }_k^{60} \mathrm{Co}$, which undergoes the following decay process: ${ }_{27}^{60} \mathrm{Co} \stackrel{k}{\rightarrow}{ }_{28}^{60} \mathrm{Ni}+\beta^{-}+\gamma$. The half-life of ${ }^{60} \mathrm{Co}$ is $1.9 \times 10^3$ days. a. What is the rate constant for the decay process? b. How long will it take for a sample of ${ }^{60} \mathrm{Co}$ to decay to half of its original concentration?

What is meant by a diffusion-controlled reaction?

What is a transition state? How is the concept of a transition state used in activated complex theory?

One issue confronting the use of ${ }^{14} \mathrm{C}$ decay (halflife of 5760 years) to date materials is that of obtaining a standard. One approach to this issue is found in the field of dendrochronology or using tree rings to determine age. Using this approach, tree materials dating back 10,000 years have been identified. Assuming you had a sample of such a tree in which the number of decay events was $15.3$ decays per minute before decomposition, what would the decays per minute be in the present day?

In a temperature-jump experiment, why does a change in temperature result in a corresponding change in equilibrium?