Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 23: Problem 70

(a) A compound with formula $\mathrm{RuCl}_{3} \cdot 5 \mathrm{H}_{2} \mathrm{O}$ is dissolved in water, forming a solution that is approximately the same color as the solid. Immediately after forming the solution, the addition of excess \(\mathrm{AgNO}_{3}(a q)\) forms 2 mol of solid \(\mathrm{AgCl}\) per mole of complex. Write the formula for the compound, showing which ligands are likely to be present in the coordination sphere. (b) After a solution of \(\mathrm{RuCl}_{3} \cdot 5 \mathrm{H}_{2} \mathrm{O}\) has stood for about a year, addition of \(\mathrm{AgNO}_{3}(a q)\) precipitates 3 mol of AgCl per mole of complex. What has happened in the ensuing time?

Short Answer

Expert verified
The initial complex formula is \([\mathrm{RuCl}_{2}(\mathrm{H}_{2}\mathrm{O})_{2}]Cl\cdot 3\mathrm{H}_{2}\mathrm{O}\) after the immediate reaction with \(\mathrm{AgNO}_{3}\). After standing for about a year, the complex formula changes to \([\mathrm{RuCl}_{3}(\mathrm{H}_{2}\mathrm{O})]Cl_{2}\cdot 4\mathrm{H}_{2}\mathrm{O}\) due to the replacement of a water ligand by a Cl atom in the coordination sphere.

Step by step solution

01

Analyze the immediate reaction with AgNO3

The initial compound has the formula \(\mathrm{RuCl}_{3} \cdot 5 \mathrm{H}_{2} \mathrm{O}\). When the compound is dissolved in water and reacts with an excess of AgNO3, it forms 2 moles of solid \(\mathrm{AgCl}\) per mole of complex. Based on this information, we can infer that there are 2 Cl atoms in the coordination sphere of the Ru complex.
02

Propose the complex formula after initial reaction with AgNO3

Since two of the Cl atoms in the original compound \(\mathrm{RuCl}_{3} \cdot 5 \mathrm{H}_{2} \mathrm{O}\) are coordinated to the Ru atom, we can propose the complex formula to be: \([\mathrm{RuCl}_{2}(\mathrm{H}_{2}\mathrm{O})_{2}]Cl\cdot 3\mathrm{H}_{2}\mathrm{O}\).
03

Analyze the reaction after a year of standing

After the solution has stood for about a year, we are informed that the addition of \(\mathrm{AgNO}_{3}(a q)\) precipitates 3 moles of \(\mathrm{AgCl}\) per mole of complex. This information suggests that an additional Cl atom in the coordination sphere of the Ru complex has been replaced.
04

Determine the change in the coordination sphere

We infer that a water ligand in the coordination sphere has been replaced by a Cl atom, as the number of moles of \(\mathrm{AgCl}\) precipitated has increased. The coordination sphere of the complex after this change will contain 3 Cl atoms instead of 2.
05

Propose the final complex formula

Accounting for the change in the coordination sphere of the Ru complex, we can now propose the complex formula to be: \([\mathrm{RuCl}_{3}(\mathrm{H}_{2}\mathrm{O})]Cl_{2}\cdot 4\mathrm{H}_{2}\mathrm{O}\). This is the formula of the complex after it has stood for about a year and then reacted with \(\mathrm{AgNO}_{3}(a q)\).

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.

Start your free trial

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

Sketch the structure of the complex in each of the following compounds and give the full compound name: (a) $c i s-\left[\operatorname{PtBr} \mathrm{Cl}\left(\mathrm{NO}_{2}\right)_{2}\right]^{2-}$ (b) $\left[\mathrm{Mn}(\mathrm{CO})_{3}\left(\mathrm{C}_{6} \mathrm{H}_{6}\right)\right]^{+}$ (c) $\left.c i s-\left[\mathrm{Cr} \mathrm{Cl}_{4}\right)\left(\mathrm{OH}_{2}\right)_{2}\right]^{-}$ (d) trans-[Co(OH)(en) \(\left._{2} \mathrm{Cl}\right]^{+}\)

The lanthanide contraction explains which of the following periodic trends? (a) The atomic radii of the transition metals first decrease and then increase when moving horizontally across each period. (b) When forming ions the period 4 transition metals lose their \(4 s\) electrons before their \(3 d\) electrons. (c) The radii of the period 5 transition metals (Y-Cd) are very similar to the radii of the period 6 transition metals (Lu-Hg).

Draw the structure for $\mathrm{Pt}\left(\mathrm{C}_{2} \mathrm{O}_{4}\right)\left(\mathrm{NH}_{3}\right)_{2}$ and use it to answer the following questions: (a) What is the coordination number for platinum in this complex? (b) What is the coordination geometry? (c) What is the oxidation state of the platinum? (d) How many unpaired electrons are there? [Sections 23.2 and 23.6\(]\)

Consider the following three complexes: \(\left(\right.\) Complex 1) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{SCN}\right]^{2+}$ \(\left(\right.\) Complex 2) $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}_{3}\right]^{2+}$ \(\left(\right.\) Complex 3) \(\mathrm{CoClBr} \cdot 5 \mathrm{NH}_{3}\) Which of the three complexes can have (a) geometric isomers, (b) linkage isomers, (c) optical isomers, (d) coordination-sphere isomers?

(a) A complex absorbs photons with an energy of $4.51 \times 10^{-19} \mathrm{~J}$. What is the wavelength of these photons? (b) If this is the only place in the visible spectrum where the complex absorbs light, what color would you expect the complex to be?
See all solutions

Recommended explanations on Chemistry Textbooks

Making Measurements

Read Explanation

Inorganic Chemistry

Read Explanation

Chemical Reactions

Read Explanation

Kinetics

Read Explanation

Nuclear Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation
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