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Chapter

Cover f-Block Chemistry

Binary compounds: oxides and halides  

This chapter examines binary compounds, looking at lanthanoid and actinoid oxides and halides. Binary oxides and halides of the f-elements are important as starting materials for manufacture of the elements, as starting materials for synthesis of other compounds and complexes, and as materials in their own right. For example, CeO2 has a very rich chemistry and this is a result of the accessibility of both +3 and +4 oxidation states for Ce, and this results in practical applications. The oxide chemistry for the actinoid elements from Pa to Pu is also very rich as a result of the accessibility of a range of oxidation states. Structures and stoichiometries of oxides and halides reflect trends in ionic radii and in relative stabilities of oxidation states.

Chapter

Cover Thrive in Cell Biology

Mitochondria, hydrogenosomes, and mitosomes  

This chapter outlines the functions of the matrix of mitochondria as the site of oxidations or decarboxylation of pyruvate, the production of heat in some thermogenic tissues, and the formation of iron-sulfphur proteins. It talks about the inner mitochondrial membrane (IMM), which is the site of the production of ATP by oxidative phosphorylation and for initiating apoptosis. It also details the evolution of mitochondria, which is thought to have occurred from primitive bacteria that were endosymbionts of early eukaryotic cells that occurred at least 2000 million years ago. The chapter describes hydrogenosomes as spherical-shaped organelles of approximately 1-2 ?m diameter which are able to produce molecular or dihydrogen. It examines mitosomes which are found in a number of unicellular eukaryotic species that occupy anaerobic environmental niches and resemble hydrogenosomes in appearance.

Chapter

Cover Aquatic Environmental Chemistry

Oxidation and reduction  

This chapter focuses on oxidation and reduction. When the muddy sediments at the bottom of a river or lake are disturbed, two things are often noticed. First, there is a smell of rotten eggs, indicative of the generation of hydrogen sulfide. Secondly, the colour of the sediment may change from a red-brown at the surface to a dark brown-black below. Both of these observations are linked to a lack of oxygen. In purely chemical terms, the absence of oxygen in these sediments has resulted in the reduction of sulfur(VI) to sulfur(-II); that the reduction has been carried out by bacteria does not necessarily alter the chemical result. It is not only the sediments which can become devoid of oxygen. The water in lakes, and even the bottom waters of fjords, can reach this state if the oxygen is consumed by organisms and if the chemical processes faster than it can be replaced.

Chapter

Cover Organonitrogen Chemistry

Nitroso compounds  

This chapter looks into the synthesis and reactions of N-oxides. The N-heteroatom bond of N-oxides is not introduced intact in the synthesis of compounds. However, it is delivered in an oxidation reaction. It notes peracid as the usual oxidant which is either used directly or generated in place from a carboxylic acid or hydrogen peroxide mixture. It also highlights how N-oxides are vital for aeffecting syn eliminations as the N-oxide acts similarly to a quaternary ammonium compound with an internal alkoxide base. Finally, the chapter uses diagrams to emphasise how the synthesis and reactions occurs.

Book

Cover Oxidation and Reduction in Organic Synthesis
Oxidation and Reduction in Organic Synthesis looks in detail at the topic of organic synthesis. The manipulation of functional groups by oxidative or reductive processes is central to organic chemistry, the text argues. This book provides a clear summary of oxidative and reductive processes, emphasizing general principles and common factors, and shows the applications of these reactions in organic synthesis. After an initial introduction, chapters cover enaitioselective oxidation, oxidation reactions in synthesis, reduction reactions, and enaitioselective reduction.

Chapter

Cover Oxidation and Reduction in Organic Synthesis

Introduction  

This introductory chapter provides an overview of the processes of oxidation and reduction. Oxidation and reduction together are themes that run through the very core of organic chemistry. Oxidation of an organic substrate may be defined as the addition of oxygen, the removal of hydrogen, or the removal of electrons from that compound. Similarly, reduction can be defined as the removal of oxygen, the addition of hydrogen, or the addition of electrons to an organic substrate. The classification of organic compounds into oxidation states is difficult and inconsistencies abound; and although we can devise a system for achieving this classification, it is not particularly useful to organic chemists. Instead, organic chemists find it convenient to place functional groups into five different categories (or levels) depending upon the level of oxidation contained within.

Chapter

Cover The Mechanisms of Reactions at Transition Metal Sites

The oxidative-addition reaction  

This chapter focuses on the oxidative-addition reaction of alkyl halides, wherein there is a simultaneous increase in the formal oxidation state of the metal and in its coordination number. It highlights the important aspect of the oxidative-addition reaction, which provides that ‘oxidative-addition’ does not describe the mechanism of a reaction but is just a stoichiometric definition of the result of the reaction. It also reviews the simple interaction between a metal site and an alkyl halide, which results in the oxidative-addition of the latter as the metal site acts as a nucleophile with respect to the carbon centre. The chapter discusses the analogous oxidative-addition reactions of H2. It looks at two different geometries for the transition state of the reaction with RX that have different stereochemical consequences on the reaction in relation to the alkyl group and metal site.

Chapter

Cover Chemistry of the First-row Transition Metals

Metals and solid compounds  

This chapter describes the elements encountered within the crust, wherein iron is fourth after oxygen, silicon, and aluminum that comprises about 6% of the total crustal composition. It discusses first-row transition elements, which includes titanium and manganese. It also talks about the majority of the elements that occur in minerals, such as oxides, hydrated oxides, and carbonates, including principal minerals and other sources of the elements. The chapter talks about vanadium that is found naturally in some living systems, particularly sea squirts, tunicates, and some mushrooms. It looks at trace amounts of chromium, which are responsible for the characteristic colours of ruby and emerald.

Chapter

Cover Inorganic Materials Chemistry

Transition metal oxides  

This chapter evaluates transition metal oxides, reviewing binary transition metal oxide structures. The structure of many binary oxides can be predicted on the basis of the relative sizes of the metal and oxide ions and filling of holes in a close peaked oxide lattice. Such predictions of structure are more difficult for ternary phases. The combination of two or more metals in an oxide generates a wealth of structural possibilities dependent on the relative sizes of the two metal ions and the oxide ion. In addition, the stoichiometry of the ternary oxide may be changed by varying the proportions of the two component oxides and, for transition and lanthanide elements, the oxidation state. The chapter then looks at the perovskite structure, insertion compounds, lithium niobate, the spinel structure, and the K2NiF4 structure.

Chapter

Cover Human Physiology

Alveolar ventilation and blood gas exchange  

This chapter examines the main function of the respiratory system, which is to provide the cells of the body with oxygen for the generation of metabolic energy and to remove the carbon dioxide produced by oxidative metabolism. To do so, it must have a means of transporting these two gases to and from the tissues and exchanging them with the atmospheric air. It focuses on the gas exchange in the alveoli and the matching of blood flow to the availability of oxygen. The chapter details the transport of oxygen and carbon dioxide by the blood. Broadly, the respiratory system can be considered to consist of two parts: the conducting airways and the area of gas exchange.

Chapter

Cover Inorganic Chemistry

The d-block elements  

This chapter focuses on the d-block elements, which are all metallic and which have chemical properties crucial to biology, industry, and many aspects of contemporary research. This includes the Group 3 to Group 12 elements. The chapter concentrates on specific properties of the individual elements and some of their important compounds. It describes their occurrence and recovery, highlighting that the chemically soft members of the block occur as sulfide minerals and some can be roasted in air to obtain the metal; and the more electropositive hard metals occur as oxides and are extracted by reduction. The chapter also briefly explains how metal-metal bonds arise and why mercury is toxic.

Chapter

Cover Inorganic Chemistry

Oxidation and reduction  

This chapter explains oxidation: the removal of electrons from a species;, and reduction: the addition of electrons. It provides examples of redox chemistry and -develops concepts for understanding why oxidation and reduction reactions occur, considering mainly their thermodynamic aspects. The chapter discusses the procedures for analysing redox reactions in solution, explaining that the electrode potentials of electrochemically active species provide data that are useful for determining and understanding the stability of species and solubility of salts. Furthermore, it describes procedures for displaying trends in the stabilities of various oxidation states, including the influence of pH. Then it tackles the applications of this information to environmental chemistry, chemical analysis, and inorganic synthesis. The chapter ends with a thermodynamic examination of the conditions needed for some major industrial oxidation and reduction processes, particularly the extraction of metals from their ores and new applications in clean and efficient technologies.

Chapter

Cover Making the Transition to University Chemistry

Alcohols  

This chapter focuses on alcohols (ROH) which have at least one hydroxyl group bonded to a carbon atom. Alcohols are known to undergo two reactions similar to the reactions of halogenoalkanes. Additionally, esters are formed through an alcohol's reaction to carboxylic acids. Alcohols also undergo oxidation reactions. The chapter explores the main manufacturing processes for ethanol which are fermentation and the direct hydration of ethene. It also considers the nucleophilic substitution and oxidation reactions of alcohols. The elimination reactions coincide with alcohol being dehydrated through heating with acid. However, conditions depend on the specific alcohol involved in the process as some of the alcohols could produce more than a single product.

Chapter

Cover Biochemistry and Molecular Biology

Energy release from fat  

This chapter shows the way that energy is released from fat involving the oxidation of fatty acids released from triacylglycerols. These are first converted into fatty acyl-Coenzyme As (CoAs). Then the acyl groups are transported into the mitochondria. The chapter emphasizes that fatty acyl-CoA cannot enter the mitochondrion, but an enzyme of the outer membrane transfers it to carnitine and a transport system transfers the acylcarnitine into the matrix where another enzyme transfers the acyl group back to CoA. In the matrix, the fatty acyl-CoA is converted into acetyl-CoA by a process called β-oxidation in which carbon atoms are released two at a time in the form of acetyl-CoA. The chapter describes the fatty acid chain of acyl-CoAs, which is dehydrogenated by a series of enzymes that produce β-ketoacyl-CoAs. Acetyl units are split off by the enzyme ketoacyl-CoA thiolase, which attaches each to CoASH and releases acetyl-CoA.

Chapter

Cover Chemistry3

s-Block chemistry  

This chapter discusses the s-block, which is the collective name for the elements of Groups 1 and 2 of the Periodic Table and comes from the valence electronic configurations of the elements. The ions of sodium, potassium, magnesium, and calcium are all essential for life, and many Group 1 and 2 compounds are important industrially. The chapter details the preparation, uses, and reactivity of the s-block elements, including the synthesis and reactions of the s-block oxides, hydroxides, and halides. It describes changes in the solubility of s-block compounds and explains these using the lattice Gibbs energies and hydration Gibbs energies. It also cites examples of s-block coordination complexes and confirms why Group 2 coordination chemistry is more prevalent than Group 1 coordination chemistry.

Chapter

Cover Making the Transition to University Chemistry

Transition Metals 2  

This chapter focuses on the first row of transition metals ranging from tin to copper. It clarifies how scandium and zinc are not transition metals due to their oxidation states and d subshells. The group has d-block elements with at least one stable ion that has a partially-filled d subshell. Transition metals showcase variable oxidation states. An acidic solution with a reductant can reduce a transition metal ion, while an alkaline solution with an oxidant could oxidize a transition metal. The stability of the high oxidation states can be significantly increased in alkaline solutions. The chapter also notes how transition metals are often used as catalysts.

Chapter

Cover Essentials of Inorganic Chemistry 1

Orbitals to oxidation state  

This chapter examines atomic orbitals. An atomic orbital is the wavefunction of an electron in an atom; its square gives the probability of finding the electron at that point. The Schrödinger solution defines the wave equation for the electron in the hydrogen atom as a product of a radial and angular part. The chapter then looks at organometallic compounds before considering the oxidation state, which is a formal device for partitioning electrons in a molecule in a chemically intelligent way. The oxidation state of an atom in a compound is the charge which would result if the electrons in each bond to that atom were assigned to the more electronegative atom.

Chapter

Cover Chemical Structure and Reactivity

Main-group chemistry  

This chapter focuses on the chemistry of what are usually called the ‘main group’ elements, which are those in the s- and p-blocks. Although the main group elements are very diverse, ranging from the most typical metals through semi-metals to the most typical non-metals, the reason that they are often considered together is that these elements show a gradual variation in their chemical properties which can largely be understood using a small number of key concepts. The elements from Groups 12–18 show variable oxidation states. For a given element, the highest oxidation state of (group number minus 10) is often only shown by the fluoride or oxide of that element. Metal halides may be hydrolysed, depending on the acidity of the aquo ions; hydrolysis of non-metal halides gives acidic solutions. Meanwhile, metal oxides tend to be basic or amphoteric while non-metal oxides tend to be acidic.

Chapter

Cover Bioinorganic Chemistry

Photosynthesis  

This chapter looks at the overall involvement of metal centres in photosynthesis, specifically discussing the central role of the chlorophylls on the one hand, and of the oxygen-evolving centre on the other hand. It first gives an overview of the Great Oxygenation Event which happened about 2.4 Ga ago, when photosynthetically active cyanobacteria, also called blue-green algae, started to produce — and to release into the atmosphere — more oxygen than could be eliminated by oxidation processes, such as oxidative decay of organics, or the conversion of ferrous to ferric iron, sulfide to sulfate, ammonia to nitrate, and so forth. This change forced organisms that failed to adapt to the novel situation into oxygen-free niches. Emphasizing that more than one hundred proteins are involved in the global regulation of the photosynthetic machinery, steering over 50 distinct chemical transformations, the chapter looks at relevant reaction pathways. Furthermore, it tackles artificial photosynthesis.

Chapter

Cover The Biochemical Basis of Sports Performance

Middle-distance events  

This chapter evaluates the relative contributions to energy metabolism from phosphocreatine breakdown, anaerobic glycolysis, and carbohydrate oxidation during middle-distance running. Oxidative metabolism makes the major contribution to energy production when the exercise duration exceeds about one to two minutes. However, at least for exercise intensities that can be sustained for less than about ten minutes, the rate at which energy must be supplied to the working muscles exceeds the maximum rate of the oxidative processes. The chapter uses the example of the middle-distance track runner to describe the metabolic processes occurring and to consider the causes of fatigue and potential limitations to performance in events taking place over this time scale. The chapter then looks at the glycolytic pathway and the regulation of glycolysis.