lighter; carbon; carbocation; species; associative; pathways
example: Elements lighter than carbon (B, Be, Li) as well as Al and Mg often form electron-deficient structures that are electronically akin to carbocations. Such electron-deficient species tend to react via associative pathways.
Octet rule
heavier elements; compounds; mechanism; reaction; organic compounds
D-orbitals role
bounding; pathways; to influence; rates of ligand substitution; rates of ligand dissociation; coordination chemistry
Free and bound water exchange
mechanistic transition metal chemistry; kinetic lability; prototypical complexes; isotopically enriched water; by 20 orders; lanthanide complexes; slowest
Atom-transfer reaction
two classes; oxidative addition; reductive elimination; electron transfer; self-exchange; generative reaction; permanganate; relative manganate
Exercise 2. Ask questions to the given answers:
1) Question: ___________________________________________?
Answer: An overarching aspect of mechanistic transition metal chemistry is the kinetic lability of the complex.
2) Question: ___________________________________________?
Answer: Redox reactions are relevant for the transition elements.
3) Question: ___________________________________________?
Answer: The mechanisms of their reactions differ from organic compounds for this reason.
III. Writing Exercises:
Exercise 1. Compose a story on one of the topics (up to 40 words):
The connection of inorganic and organic chemistry
Associative and dissociative pathways
Redox reactions
Lesson 8
Read the text: Mechanistic and Synthetic Inorganic Chemistry. Part II
Reactions at ligands
Coordinated ligands display reactivity distinct from the free ligands. For example, the acidity of the ammonia ligands in [Co(NH3)6]3+ is elevated relative to NH3 itself. Alkenes bound to metal cations are reactive toward nucleophiles whereas alkenes normally are not. The large and industrially important area of catalysis hinges on the ability of metals to modify the reactivity of organic ligands. Homogeneous catalysis occurs in solution and heterogeneous catalysis occurs when gaseous or dissolved substrates interact with surfaces of solids. Traditionally homogeneous catalysis is considered part of organometallic chemistry and heterogeneous catalysis is discussed in the context of surface science, a subfield of solid state chemistry. But the basic inorganic chemical principles are the same. Transition metals, almost uniquely, react with small molecules such as CO, H2, O2, and C2H4. The industrial significance of these feedstocks drives the active area of catalysis.
Synthetic inorganic chemistry
Although some inorganic species can be obtained in pure form from nature, most are synthesized in chemical plants and in the laboratory.
Inorganic synthetic methods can be classified roughly according the volatility or solubility of the component reactants. Soluble inorganic compounds are prepared using methods of organic synthesis. For metal-containing compounds that are reactive toward air, Schlenk line and glove box techniques are followed. Volatile compounds and gases are manipulated in vacuum manifolds consisting of glass piping interconnected through valves, the entirety of which can be evacuated to 0.001 mm Hg or less. Compounds are condensed using liquid nitrogen (b.p. 78K) or other cryogens. Solids are typically prepared using tube furnaces, the reactants and products being sealed in containers, often made of fused silica (amorphous SiO2) but sometimes more specialized materials such as welded Ta tubes or Pt boats. Products and reactants are transported between temperature zones to drive reactions.
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I. Reading Exercises:
Exercise 1. Read and memorize using a dictionary:
coordinated ligands, acidity, alkenes, reactivity, homogeneous catalysis, solution, dissolved substrate, surface science, volatility, solubility, soluble inorganic compounds, metal-containing compounds, liquid nitrogen, cryogens, fused silica
Exercise 2. Answer the questions:
1) How are solids prepared in synthetic inorganic chemistry?
2) What differs coordinated ligands from the free ligands?
3) How are synthetic compounds made?
4) What is the most important ability of metals used for producing catalysts?
Exercise 3. Open brackets choosing the right words:
Traditionally (organic/homogeneous) catalysis is considered part of organometallic chemistry and (active/heterogeneous)z:\wiki\Heterogeneous_catalysis catalysis is discussed in the context of surface z:\wiki\Surface_chemistry(science/technology), a subfield of (liquid/solid) state chemistry.
II. Speaking Exercises:
Exercise 1. Describe acidity; transition metals; inorganic synthetic methods; volatile compounds; temperature zone using the suggested words and expressionsas in example:
Acidity
ammonia ligands; relative; alkenes; metal cations; nucleophiles
example: The acidity of the ammonia ligands in [Co(NH3)6]3+ is elevated relative to NH3 itself. Alkenes bound to metal cations are reactive toward nucleophiles whereas alkenes normally are not.
Transition metals
small molecules; significance; feedstocks; active area; catalysts
