As discussed in the "Chemistry Put to Work" box in Section 10.8 , enriched uranium can be produced by effusion of gaseous \(\mathrm{UF}_{6}\) across a porous membrane. Suppose a process were developed to allow effusion of gaseous uranium atoms, U(g). Calculate the ratio of effusion rates for \(^{235} \mathrm{U}\) and \(^{238} \mathrm{U},\) and compare it to the ratio for \(\mathrm{UF}_{6}\) given in the essay.

Short Answer

Expert verified
The ratio of effusion rates for gaseous uranium isotopes \(^{235}\mathrm{U}\) and \(^{238}\mathrm{U}\) is approximately 1.0063, which is slightly higher but still quite comparable to the given ratio of 1.0043 for \(\mathrm{UF_{6}}(g)\) containing these isotopes. This suggests that the effusion process would be more efficient for separating uranium isotopes in the gaseous form, although the difference is not significant.

Step by step solution

01

Recall Graham's law of effusion

Graham's law of effusion states that the rate of effusion of a gas is inversely proportional to the square root of its molar mass. Mathematically, it is expressed as: $$\frac{Rate_A}{Rate_B} = \sqrt{\frac{M_B}{M_A}}$$ where Rate_A and Rate_B are the effusion rates of gas A and B respectively, and M_A and M_B are their molar masses.
02

Identify the given information

We are given the two isotopes of uranium: 1. \(^{235}\mathrm{U}\) 2. \(^{238}\mathrm{U}\) We need to find the ratio of effusion rates for these isotopes.
03

Apply Graham's law of effusion

Applying the formula from Step 1: $$\frac{Rate_{^{235}\mathrm{U}}}{Rate_{^{238}\mathrm{U}}} = \sqrt{\frac{M_{^{238}\mathrm{U}}}{M_{^{235}\mathrm{U}}}$$
04

Calculate the effusion rates ratio

Now we can plug in the molar masses of the two uranium isotopes: $$\frac{Rate_{^{235}\mathrm{U}}}{Rate_{^{238}\mathrm{U}}} = \sqrt{\frac{238 \mathrm{g/mol}}{235 \mathrm{g/mol}}}$$ Solving for the ratio: $$\frac{Rate_{^{235}\mathrm{U}}}{Rate_{^{238}\mathrm{U}}} = \sqrt{\frac{238}{235}} = 1.0063$$ The ratio of effusion rates for \(^{235}\mathrm{U}\) and \(^{238}\mathrm{U}\) is approximately 1.0063.
05

Compare the ratio for uranium isotopes to 𝑈𝐹6 ratios

The ratio of effusion rates for \(\mathrm{UF_{6}}(g)\) containing \(^{235}\mathrm{U}\) and \(^{238}\mathrm{U}\) is given in the essay as 1.0043. The ratio for gaseous uranium isotopes, 1.0063, is slightly higher but still quite comparable to the ratio for \(\mathrm{UF_{6}}(g)\). This indicates that the effusion process would be more efficient for separating the uranium isotopes in the gaseous form, but the difference is not significant.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

(a) Are you more likely to see the density of a gas reported in \(\mathrm{g} / \mathrm{mL}, \mathrm{g} / \mathrm{L},\) or \(\mathrm{kg} / \mathrm{cm}^{3} ?(\mathbf{b})\) Which units are appropriate for expressing atmospheric pressures, \(\mathrm{N}, \mathrm{Pa},\) atm, kg/m \(^{2} ?\) (c) Which is most likely to be a gas at room temperature and ordinary atmospheric pressure, \(\mathrm{F}_{2}, \mathrm{Br}_{2}, \mathrm{K}_{2} \mathrm{O} .\)

Gas pipelines are used to deliver natural gas (methane, \(\mathrm{CH}_{4}\) ) to the various regions of the United States. The total volume of natural gas that is delivered is on the order of \(2.7 \times 10^{12} \mathrm{L}\) per day, measured at STP. Calculate the total enthalpy change for combustion of this quantity of methane. (Note: Less than this amount of methane is actually combusted daily. Some of the delivered gas is passed through to other regions.)

Magnesium can be used as a "getter" in evacuated enclosures to react with the last traces of oxygen. (The magnesium is usually heated by passing an electric current through a wire or ribbon of the metal.) If an enclosure of 0.452 L. has a partial pressure of \(\mathrm{O}_{2}\) of \(3.5 \times 10^{-6}\) torr at \(27^{\circ} \mathrm{C},\) what mass of magnesium will react according to the following equation? $$2 \mathrm{Mg}(s)+\mathrm{O}_{2}(g) \longrightarrow 2 \mathrm{MgO}(s)$$

Table 10.3 shows that the van der Wals \(b\) parameter has units of L/mol. This means that we can calculate the sizes of atoms or molecules from the \(b\) parameter. Refer back to the discussion in Section \(7.3 .\) Is the van der Waals radius we calculate from the \(b\) parameter of Table 10.3 more closely associated with the bonding or nonbonding atomic radius discussed there? Explain.

Determine whether each of the following changes will increase, decrease, or not affect the rate with which gas molecules collide with the walls of their container: (a) increasing the volume of the container, (b) increasing the temperature, (c) increasing the molar mass of the gas.

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free