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Using Lindlar's catalyst results in syn addition to form a cis alkene. Using lithium in liquid ammonia yields a trans alkene Ozonolysis Preparation of alkynes

Adding HBr to a diene forms a 1-2 adduct (top) or a 1-4 adduct (bottom) Adding Br2 to a diene forms a 1-2 adduct (top) or a 1-4 adduct (bottom)

Creates a vicinal halide (anti addition) syn addition Creates an alkyl halide following Markovnikov's ru Creates a Markovnikov alcohol Creates an anti-Markovnikov alcohol Alkenes react with peracides to form epoxodies/oxiranes through a syn addition Yields two carbonyl compounds. React with cold potassium permanganate to form vicinal diols through a syn addition. Eliminates water to form the most stable alkene (use Zaitsev's rule) Eliminates HX to form the most stable alkene (anti elimination) (use Zaitsev's rule)

Balancing Redox 4 of 6 Reactions - Balance the Charge Next, balance the charges in each half-reaction so that the reduction half-reaction consumes the same number of electrons as the oxidation half-reaction supplies. This is accomplished by adding electrons to the reactions: 2 I - → I 2 + 2e - 5 e - + 8 H + + MnO 4 - → Mn 2+ + 4 H 2 O Now multiple the oxidations numbers so that the two half-reactions will have the same number of electrons and can cancel each other out: 5(2I - → I 2 +2e - ) 2(5e - + 8H + + MnO 4 - → Mn 2+ + 4H 2 O) Balancing Redox 5 of 6 Reactions - Add the Half-Reactions Now add the two half-reactions: 10 I - → 5 I 2 + 10 e - 16 H + + 2 MnO 4 - + 10 e - → 2 Mn 2+ + 8 H 2 O This yields the following final equation: 10 I - + 10 e - + 16 H + + 2 MnO 4 - → 5 I 2 + 2 Mn 2+ + 10 e - + 8 H 2 O Get the overall equation by canceling out the electrons and H 2 O, H + , and OH - that may appear on both sides of the equation: 10 I - + 16 H + ...

Balancing Redox Reactions 1 of 6- Half-Reaction Method To balance redox reactions , assign oxidation numbers to the reactants and products to determine how many moles of each species are needed to conserve mass and charge. First, separate the equation into two half-reactions, the oxidation portion and the reduction portion. This is called the half-reaction method of balancing redox reactions or the ion-electron method . Each half-reaction is balanced separately and then the equations are added together to give a balanced overall reaction. We want the net charge and number of ions to be equal on both sides of the final balanced equation. For this example, let's consider a redox reaction between KMnO 4 and HI in an acidic solution: MnO 4 - + I - → I 2 + Mn 2+ Balancing Redox Reactions 2 of 6- Separate the Reactions Separate the two half reactions: I - → I 2 MnO 4 - → Mn 2+ Balancing Redox 3 of 6Reactions - Balance the Atoms To balance the atoms of each half-r...

Virtual Chemistry Text Table of Contents Oxidation and reduction reactions go hand in hand, which is why they are also called redox reactions. Acids and bases may be thought of as reactions involving hydrogen, or protons, while redox reactions tend to be concerned with electron gain and loss.

Three-Dimensional Arrangement of Atoms in a Molecule There are two electron pairs around the central atom in a molecule with linear molecular geometry, 2 bonding electron pairs and 0 lone pairs. The ideal bond angle is 180°. Ben Mills Molecular geometry or molecular structure is the three-dimensional arrangement of atoms within a molecule. It is important to be able to predict and understand the molecular structure of a molecule because many of the properties of a substance are determined by its geometry. The Valence Shell, Bonding Pairs, and VSEPR Model The outermost electrons of an atom are its valence electrons. The valence electrons are the electrons that are most often involved in forming bonds and making molecules. Pairs of electrons are shared between atoms in a molecule and hold the atoms together. These pairs are called "bonding pairs". One way to predict the way electrons within atoms will repel each other is to apply the VSEPR (valence-shell electron-pair ...

Naming cyclic alkanes First you would count the longest carbon chain. You can see that the "cyclic" ring has 8 carbons, so it's octane. Since it's a cyclic ring, you call it a "cyclo" alkane. Hence, the main part of the molecule would be called cyclooctane. The substituent is called a methyl group, so you get the name methylcyclooctane. Now, the hard part of this is figuring out numberings. You can pick ANY carbon to be "1," so we'll conveniently choose the carbon that the methyl is on as methylcyclooctane. It wouldn't matter if the methyl group was on the top right carbon, because it would still be methylcyclooctane, because you could rotate that molecule to get the one above. Now, let's try two substituents. We again know it's a cyclooctane, but the problem arises in how to number the substituents. We could name this 1-methyl-3-ethylcyclooctane, or 1-ethyl-3-methylcyclooctane. We name it 1-ethyl-3-methylcyclooctane because of the ...

... not that actually want mosquitoes to bite your friends, but I think you will agree you don't want to be bitten. Here's a list of things that attract mosquitoes. If you want to avoid an encounter with the vampiric swarm you can avoid doing any of these things yourself or you can encourage those around you to do them. Whatever works. Wear Dark Clothing Many mosquitoes use vision to locate hosts from a distance. Dark clothes and foliage are initial attractants. Exercise You give off more carbon dioxide when you are hot or have been exercising. A burning candle or other fire is another source of carbon dioxide. Eat Bananas and French Fries You release more lactic acid when you have been exercising or after eating certain foods (e.g., salty foods, high-potassium foods). Wear Perfume or Cologne In addition to perfumes, hair products, and scented sunscreens, watch for the subtle floral or fruity fragrances from fabric softeners and dryer sheets. Have Cold Hands Mosquitoes are attr...

Learning how to name alkanes will be crucial in your understanding of organic chemistry. All organic compounds are named following a certain set of rules set out by the IUPAC. By memorizing these rules, you should be able to name all compounds. To name alkanes.... (follow these set of rules) 1.) Count the longest carbon chain If the carbon chain is: 1 carbon: named "methane" 2 carbons: named "ethane" 3 carbons: named "propane" 4 carbons: named "butane" 5 carbons: named "pentane" 6 carbons: named "hexane" 7 carbons: named "heptane" 8 carbons: named "octane" 9 carbons: named "nonane" 10 carbons: named "decane" Note that organic chemists, being lazy, will often not label hydrogens or carbons. For instance, would be hexane (each of the "points" is assumed to be a carbon) 2.) Number the carbon chain, starting with the end closest to the substituent. Always try to get the lowest numb...

All single chain hydrocarbons will combust into carbon dioxide and water completely Halogenation of an alkane. This reaction takes an unreactive molecule (methane) and makes it very reactive (chloromethane).

Two extremily common reactions in Organic Chemistry are substitution and elimination reactions. We are going to cover four basic reactions, E1, E2, SN1, and SN2. These reactions all compete with each other so be sure to pay attention to which conditions fovor each reaction. SN2 The most common is called an SN2 reaction. It is a simple nucleophilic attack of a nucleophile onto an electrophilic carbon. This attack causes and inversion of absolute configuration of the carbon center.   SN2 Nucleophilic Substitution causes inversion of configuration: (best in polar aprotic solvents, strong nucleophiles and good leaving groups.)  Going from (R) to (S) SN1 If Carbon is tertiary and nucleophile is weak then it undergoes SN1 reaction: j has same products as SN2 but is racemised and best in polar protic solvent and the reaction is 1st order, not 2nd... Remember: -racemization is when there is the absolute configuration of the carbon center is not either retaine...

Get Science Fair Project Ideas It can be a challenge to come up with a science fair project idea. There is fierce competition to come up with the coolest idea, plus you need a topic that is considered appropriate for your educational level. I've arranged science fair project ideas by topic, but you might like to take a look at ideas according to education level. A well-designed project at the college level can open the door to future educational and career opportunities, so it pays to put some thought and effort into your topic. Answer a question, test a hypothesis. College students usually have a semester to complete their project, so you have some time to plan and conduct your research. The goal at this level is to find an original topic. It doesn't have to be something complicated or time-consuming. Also, appearances count. Aim for professional-quality images and presentation. Handwritten work and drawings won't work as well as a printed report or poster with photographs...

Get Science Fair Project Ideas It can be challenging to think of a good project idea. H. Berends, stock.xchng I t can be a challenge to come up with a science fair project idea. There is fierce competition to come up with the coolest idea, plus you need a topic that is considered appropriate for your educational level. I've arranged science fair project ideas by topic, but you might like to take a look at ideas according to education level. Elementary School Science Fair Project Tips Elementary school projects aren't supposed to be rocket science (though of course they could be). Look for a project that you can do over a fairly short time span, such as over a weekend. Keep in mind, judges will disqualify you if they suspect your parents did the project and not you, so though you may get help from adults, be sure the project is really yours. Resist the temptation to make a display or do a demonstration. Try to answer a question or solve a problem. Can you predict what things wil...

Chemistry is the study of matter and the interactions between different types of matter and energy. The fundamental building block of matter is the atom. An atom consists of three main parts: protons, neutrons, and electrons. Protons have a positive electrical charge. Neutrons have no electrical charge. Electrons have a negative electrical charge. Protons and neutrons are found together in what is called the nucleus of the atom. Electrons circle around nucleus.                                                     Chemical reactions involve interactions between the electrons of one atom and the electrons of another atom. Atoms which have different amounts of electrons and protons have a positive or negative electrical charge and are called ions. When atoms bond together, they can make larger building blocks of matter called molecules. All matter consists of particles called atoms. Here are some useful facts about atoms: Atoms cannot be divided using chemicals. They do consist of parts, w...

There are several methods of defining acids and bases. While these definitions don't contradict each other, they do vary in how inclusive they are. Antoine Lavoisier, Humphry Davy, and Justus Liebig also made observations regarding acids and bases, but didn't formalize definitions. Sulfuric acid can donate two protons or hydrogen ions in an aqueous solution. Ben Mills Svante Arrhenius acids produce H+ ions in aqueous solutions bases produce OH- ions in aqueous solutions water required, so only allows for aqueous solutions only protic acids are allowed; required to produce hydrogen ions only hydroxide bases are allowed J ohannes Nicolaus Brønsted - Thomas Martin Lowry acids are proton donors bases are proton acceptors aqueous solutions are permissible bases besides hydroxides are permissible only protic acids are allowed Gilbert Newton Lewis acids are electron pair acceptors bases are electron pair donors least restrictive of acid-base definitions Properties of Acids taste sour ...

Virtual Chemistry Text Table of Contents The citric acid and ascorbic acid in a lemon are both weak acids. There are several ways to define acids and bases. One way is to look at hydrogen ion concentration. No matter which method you choose, these categories of chemicals participate in some very important reactions. Learn about acids, bases, and pH.

>Introduction > A knowledge of basic chemistry is important for understanding just about any area of biology from the function of cells to the behavior of organisms and the ecological relationships between organisms and their environment. Indeed, chemists are fond of teasing biologists by claiming that all biology is chemistry*. While this isn't quite true, in order to make sense of the structure of cells and organisms a little chemistry goes a long way. Ball and Stick" Model of a Heme group. This group is part of a larger molecule, hemoglobin. Grey=Carbon, Blue= Nitrogen, Red= Oxygen. Hydrogens not shown. *Of course the physicists say that all chemistry is physics!

The chemical properties of an atom are determined largely by how full or empty the outer electron shell is. For example, atoms of fluorine(F), chlorine(Cl) and the other elements in that second from the last column of the periodic table need only one electron to fill the outer shell. These atoms have a very strong tendency to steal electrons from other atoms. Oxygen and sulphur have 6 electrons in their outer shell which again holds 8 maximum. Thus these elements tend to steal electrons. Elements such as Lithium(Li) Sodium(Na) and Potassium(K) on the left hand side of the periodic table have an almost empty shell and these elements readily give up those outer shell electrons to atoms such as oxygen and chlorine. Elements that tend to give up electrons to other atoms are called metals. Elements in the middle of the periodic table tend to share electrons rather than give them up or take them entirely. Many of these such as iron, copper or gold are also considered metals. The elements at ...

A chemical bond is an attraction between atoms brought about by a sharing of electrons between to atoms or a complete transfer of electrons. There are three types of chemical bonds: Ionic, Covalent and Polar covalent. In addition chemists often recognise another type of bond called a hydrogen bond. Ionic Bonds:    Ionic  bonds arise from elements with low electronegativity(almost empty outer shells) reacting with elements with high electronegativity (mostly full outer shells). In this case there is a complete transfer of electrons A well known example is table salt, sodium chloride. Sodium gives up its one outer shell electron completely to chlorine which needs only one electron to fill its shell. Thus, the attraction between these atoms is much like static electricity since opposite charges attract. Covalent bond: Ionic, Covalent, Polar covalent, Hydrogen bond .     Covalent bonds involve a complete sharing of electrons and occurrs most commonly between atoms that have partially f...

The fact that the oxygen end of a water molecule is negatively charged and the hydrogen end positively charged means that the hydrogens of one water molecule attract the oxygen of its neighbor and vice versa. This is because unlike charges attract. This largely electrostatic attraction is called a hydrogen bond and is important in determining many important properties of water that make it such an important liquid for living things. Water can also form this type of bond with other polar molecules or ions such as hydrogen or sodium ions. Further, hydrogen bonds can occurr within and between other molecules. For instance, the two strands of a DNA molecule are held together by hydrogen bonds. Hygrogen bonding between water molecules and the amino acids of proteins are involved in maintaining the protein's proper shape. This picture represents a small group of water molecules. Hydrogen bonds between unlike charges are shown as lines without arrows on the ends. The double arrowed lines ...

Water has a number of unusual properites which come about because the atoms that comprise a water molecule form apolar covalent bonds. The main properties of water that are important for living things are the following: Ice floats. Usually when a liquid freezes the solid ismore dense than the liquid. In water thesolidphase is less dense than the liquid phase under normal conditions. If ice sank, ponds and lakes would freeze solid to the bottom making things very difficult for fish and other creatures to obtain food and oxygen in the winter. Water is a great solvent especially for polar molecules of ionically bonded substances like salt. That's because the charged ends of the water molecules are attracted to the charges on other molecules. Water molecules will surround soluable molecules or ions in a hydration shell. This helps keep the molecules in solution. Many gases dissolve in water because the the combination of attractive and repulsive forces among water molecules leaves spac...

Fatty acids are organic acids which have a long chain of carbon and hydrogens attached to the carboxyl group. Oleic Acid is a common saturated fatty acid. Actually the bend in the carbon chain suggests that oleic acid is not completely saturated. I can't resist this cool looking fatty acid from Chrysanthamums. Notice the interesting triangular ring in the carbon chain. Finally this exotic looking fatty acid is vitamin A

Organic acids are very important compounds in living things. They are important components of structural molecules such as phospholipids and are an important source of energy. Organic acids have a carboxyl group and long a chain of carbons attached to it. This diagram shows formic acid, the simplest organic acid. The name formic comes from the Latin word(Formica) for ant. This acid is an important alarm and defensive compound for many ants. Acetic acid, the acid in vinegar, has one more carbon than formic acid.

Introduction Carbon is important in biology because carbon forms the "back-bone" of just about all biologically important molecules. This is because carbon forms long and sometimes complex covalently bonded structures and also because carbon compounds vary greatly in the type of interactions they have with water. For example some carbon compounds, such as most lipids, have strictly hydrophobic interactions with water, others such as sugars are hydrophilic. Still others such as proteins and phospholipids are partly hydrophobic and partly hydrophilic. 1. Diamond 2. Graphite 3. Fullerine