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Organic Chemistry
What is organic chemistry?
What are organic molecules?
What are inorganic molecules?
What are hydrocarbons?
Are you considering a degree in chemistry?
Are you are intellectually curious about how the world works?
Do you have good analytical and numerical skills?
Do you want a challenging career in a relevant and rewarding subject?
How do the prefixes and suffixes for the open chain hydrocarbons indicate their formula?
What is the difference between saturated and unsaturated carbon compounds?
What are functional groups?
What are homologous series?
What are the different types of covalent bonds found in carbons compounds? Briefly explain with examples. What are polymers?
How are polymers made?
What is a plastic?
What is Organic Chemistry?
Fossil Fuels - Crude Oil - Hydrocarbons
Introduction to organic chemistry:

Alkanes How can I list all the isomers of an alkane?
What is an alkyl group?

Common organic compounds

How is Cr(acac)3 synthesized?
What is glacial ethanoic acid?

Organic chemicals in industry

What is butyl acetate, and what is it used for?

Properties of organic compounds

Why don't melting point trends follow trends in polarity?

Tests for organic compounds

What is a spot test for alcohol?
What is a simple test for the presence of amino acids?
What kinds of nitrogen are turned into ammonium in a Kjeldahl digestion?
Fiber

What are the types of fiber?
Does fiber contain organic or inorganic molecules?
What fiber can human beings not consume?
What fiber can human beings consume?
Are consumable fibers absorbed in the human intestines?
What are inorganic molecules?
What are organic molecules?
Where are fiber used?
What are the products of various fibers?

Organic Chemistry, Biochemistry
Organic Compounds and Polymers
Biochemicals
Organic Compounds and Polymers
Hydrocarbons
    Alkanes
    Alkenes
    Alkynes
    Aromatic
Alcohols
Ethers
Aldehydes
Ketones
Carboxylic Acids
Esters
Amines
Amides
Biochemicals
Carbohydrates
Lipids
Proteins
Nucleic Acids
There are three classes of covalent bonds, mainly found in hydrocarbons compounds of the aliphatic type: Alkanes These hydrocarbons have a single covalent bond between the 'C' atoms throughout the molecule i.e., only one pair of electrons is shared between any two carbon atoms. Examples: C2H6, C3H8, C4H10 --------- image Alkenes These are aliphatic hydrocarbons in which at least one pair of 'C' atoms are linked by a double bond in the molecule. Examples: image Alkynes These are aliphatic hydrocarbons in which at least one pair of 'C' atoms are linked by a triple bond in the molecule image

Chemistry is traditionally divided into four sub-disciplines – inorganic, organic, analytical, and physical chemistry. Organic chemistry deals with molecules formed predominantly from carbon, hydrogen, oxygen, and nitrogen bonds. Owing to the strength of carbon-carbon bonds, the range and diversity of organic molecules is enormous – literally millions of molecules have been identified. Very long molecules can be made up of much smaller organic building blocks, forming polymers such as the plastics that have become ubiquitous over the last few decades. Because living organisms are made up primarily of organic molecules, organic chemistry forms the molecular foundation of the biological sciences and is intimately linked with pharmaceuticals and drug design.

On the other hand, inorganic chemistry deals with molecules composed of other elements and where carbon-carbon bonds are not as important. Typical examples are many salts, metals, semiconductors, and nanomaterials. Molecules with both metal atoms and organic sections are also biologically important – examples include vitamin molecules, haemoglobin, and chlorophyll. Both organic and inorganic chemistry often involve the synthesis of new materials with particular properties. The property desired in the new compound may be biological activity, as in pharmaceutical compounds, chemical reactivity, or a physical property such as strength, colour, or magnetism.

The analysis and quantification of chemical components of a sample is the function of analytical chemistry. Chemical analysis is increasingly important to ensure the quality of manufactured goods, and in monitoring pollutant concentrations in our air, water, and food. Very low amounts of pollutants (such as mercury or dioxins) can harm human health or the environment. Detecting and quantifying the amounts of these pollutants presents an ongoing intellectual and technical challenge.

Physical chemistry describes the physical properties, energies, and spectra of all types of molecules (whether organic or inorganic), and how rapidly chemical reactions occur. Physical chemists typically use spectroscopy or computational methods to study molecules, surfaces, and chemical reactions. Sophisticated experimental techniques are required to probe complex or fast chemical processes, such as those that occur during combustion or the reactions taking place in the atmosphere.

What are organic molecules?

What are inorganic molecules?

Fiber

What are the types of fiber?
Does fiber contain organic or inorganic molecules?
What fiber can human beings not consume?
What fiber can human beings consume?
Are consumable fibers absorbed in the human intestines?
What are inorganic molecules?
What are organic molecules?
Where are fiber used?
What are the products of various fibers?

Organic Chemistry, Biochemistry

Introduction

Organic molecules are molecules that contain carbon and hydrogen.

The four major classes of organic molecules include carbohydrates, proteins, lipids and nucleic acids.

All living things contain these organic molecules: carbohydrates, lipids, proteins, and nucleic acids. These molecules are often called macromolecules because they may be very large, containing thousands of carbon and hydrogen atoms and because they are typically composed of many smaller molecules bonded together. These four macromolecules will be discussed in the second half of this chapter..

Carbon

Carbon has four electrons in its outer shell.
Hydrogen has one electron and one proton.

Carbon can bond by covalent bonds with as many as 4 other atoms.

The diagram above shows a molecule of methane. Lines can be used to represent bonds in the shorthand formula seen in the upper right side of the diagram.

Carbon can also form double covalent (shares 2 pairs of electrons) or triple covalent bonds (shares 3 pairs).

Carbon can form 4 covalent bonds because it has 4 electrons in its outer shell. It can form the following number of bonds. Notice that in each case below, there is a total of four bonds.

* 4 single bonds
* two double bonds
* one double bond and two single bonds
* one triple and one single bond

Long chains of carbon atoms are common. The chains may be branched or form rings.

Hydrophilic and Hydrophobic

Polar and ionic molecules have positive and negative charges and are therefore attracted to water molecules because water molecules are also polar. They are said to be hydrophilic because they interact with (dissolve in) water by forming hydrogen bonds.

Nonpolar molecules are hydrophobic (means "water fearing"). They do not dissolve in water.
Nonpolar molecules are hydrophobic.
Polar and ionic molecules are hydrophilic.

Portions of large molecules may be hydrophobic and other portions of the same molecule may be hydrophilic.

Functional Groups

Organic molecules may have functional groups attached. A functional group is a group of atoms of a particular arrangement that gives the entire molecule certain characteristics. Functional groups are named according to the composition of the group. For example, COOH is a carboxyl group.

Organic chemists use the letter "R" to indicate an organic molecule. For example, the diagram below can represent a carboxylic acid. The "R" can be any organic molecule.

Some functional groups are polar and others can ionize. For example, if the hydrogen ion is removed from the COOH group, the oxygen will retain both of the electrons it shared with the hydrogen and will have a negative charge. The hydrogen that is removed leaves behind its electron and is now a hydrogen ion (proton).

If polar or ionizing functional groups are attached to hydrophobic molecules, the molecule may become hydrophilic due to the functional group. Some ionizing functional groups are: -COOH, -OH, -CO, and -NH2.

Some important functional groups are shown below.
Name Structure
Non-ionized Ionized
Hydroxyl
Carboxyl
Amino
Phosphate
Sulfhydryl
Aldehyde

Ketone

Isomers

Different molecules that are composed of the same number and kinds of atoms are called isomers. Glucose and fructose (shown below) are both C6H12O6 but the atoms are are arranged differently in each molecule. Three kinds of isomers are described below.

Structural isomers differ in their overall construction as shown above for glucose and fructose.

Geometric isomers maintain the same carbon skeleton but a double bond occurs between carbon atoms. The location of atoms bonded to a double-bonded carbon atom differs. The two molecules below are geometric isomers because the double bond cannot rotate. If the bond between the two carbon atoms below were a single bond, they would not be isomers because atoms attached by single bonds can rotate. The carbon atoms would be able to rotate from one orientation to another if the bond were a single bond.

Enantiomers are molecules that are mirror images of each other. The molecules shown below are enantiomers.

Condensation

In order to bond the two molecules shown below together, you must first remove a hydrogen from each one. This is necessary because carbon has a maximum of 4 bonds and hydrogen can have only one.

In biological systems, macromolecules are often formed by removing H from one atom and OH from the other (see the diagram below). The H and the OH combine to form water. Small molecules (monomers) are therefore joined to build macromolecules by the removal of water. The diagram below shows that sucrose (a sugar) can be produced by a condensation reaction of glucose and fructose.

Sucrose:

This is called a condensation or dehydration reaction.

Energy is required to form the bond.

Hydrolysis

This is a type of reaction in which a macromolecule is broken down into smaller molecules.

It is the reverse of condensation (above).

Macromolecules and Monomers

Many of the common large biological molecules (macromolecules) are synthesized from simpler building blocks (monomers). Each of the types of molecules listed in the table are discussed below.

Example of a Macromolecule Monomer
polysaccharide (complex carbohydrate) monosaccharide (simple sugar)
fat (a lipid) glycerol, fatty acid
protein amino acid
nucleic acid nucleotide

Carbohydrates

The general formula for carbohydrates is (CH2O)n.

Monosaccharides

Monosaccharides are simple sugars, having 3 to 7 carbon atoms. They can be bonded together to form polysaccharides.

The names of most sugars end with the letters ose.

Example: Glucose, fructose, and galactose are monosaccharides; their structural formula is C6H12O6.

Glucose and other kinds of sugars may be linear molecules as shown below but in aqueous solution they become a ring form.

There are two isomers of the ring form of glucose. They differ in the location of the OH group on the number 1 carbon atom (in red below).

The number 1 carbon atom (numbered in red above) of the linear form of glucose is attached to the oxygen on the number 5 carbon atom.

Simple sugars store energy for cells. Details concerning energy storage and release by glucose are in the chapter on cellular respiration.

Cells also use simple sugars to construct other kinds of organic molecules.

Disaccharides

Disaccharides are composed of 2 monosaccharides joined together by a condensation reaction.

Examples:

Sucrose (table sugar) is composed of glucose and fructose.

Like glucose, sucrose stores energy. Plants synthesize sucrose to transport to nonphotosynthetic parts of the plant.

Lactose is found in milk. It is formed when glucose bonds to galactose.

The digestion of carbohydrates typically involves hydrolysis reactions in which complex carbohydrates (polysaccharides) are broken down to maltose (a disaccharide). Maltose is then further broken down to produce two glucose molecules.

Polysaccharides

Monosaccharides may be bonded together to form long chains called polysaccharides.

Starch and Glycogen

Starch and glycogen are polysaccharides that function to store energy. They are composed of glucose monomers bonded together producing long chains.

Animals store extra carbohydrates as glycogen in the liver and muscles. Between meals, the liver breaks down glycogen to glucose in order to keep the concentration of glucoses in the blood stable. After meals, as glucose levels in the blood rise, it is removed from and stored as glycogen.

Plants produce starch to store carbohydrates.

Amylopectin is a form of starch that is very similar to glycogen. It is branched but glycogen has more branches. Amylose is a form of starch that is unbranched.

Below: Glycogen or Starch

Cellulose and Chitin

Cellulose and Chitin are polysaccharides that function to support and protect the organism. The cell walls of plants are composed of cellulose. The cell walls of fungi and the exoskeleton of arthropods are composed of chitin.

Cellulose is composed of beta-glucose monomers; starch and glycogen are composed of alpha-glucose. The bond orientation between the glucose subunits of starch and glycogen allows the polymers to form compact spirals. The monomers of cellulose and chitin are bonded together in such a way that the molecule is straight and unbranched. The molecule remains straight because every other glucose is twisted to an upside-down position compared to the two monomers on each side. Cellulose fibers are composed of long parallel chains of these molecules. The chains are attached to each other by hydrogen bonds between the hydroxyl groups of adjacent molecules.

Below: Cellulose

The glucose monomers of chitin (N-acetyl glucosamine) have a side chain containing nitrogen.

Cotton and wood are composed mostly of cellulose. They are the remains of plant cell walls.

Digestibility of Cellulose and Chitin

Humans and most animals do not have the necessary enzymes needed to break the linkages of cellulose or chitin.

Animals that can digest cellulose often have microorganisms in their gut that digest it for them.

Fiber is cellulose, an important component of the human diet.

Lipids

Lipids are compounds that are insoluble in water but soluble in nonpolar solvents.

Some lipids function in long-term energy storage. One gram of fat stores more than twice as much energy as one gram of carbohydrate.

Lipids are also an important component of cell membranes.

Fats and Oils (Triglycerides)

Fats and oils are composed of fatty acids and glycerol.

Fatty acids have a long hydrocarbon (carbon and hydrogen) chain with a carboxyl (acid) group. The chains usually contain 16 to 18 carbons.

Glycerol contains 3 carbons and 3 hydroxyl groups. It reacts with 3 fatty acids to form a triglyceride or fat molecule.

Fats are nonpolar and therefore they do not dissolve in water.

Saturated and Unsaturated Fat

Saturated fatty acids have no double bonds between carbons. Unsaturated fatty acids have at least one double bond. Each double bonds produces a "bend" in the molecule.

Double bonds produce a bend in the fatty acid molecule (see diagram above). Molecules with many of these bends cannot be packed as closely together as straight molecules, so these fats are less dense. As a result, triglycerides composed of unsaturated fatty acids melt at lower temperatures than those with saturated fatty acids. For example, butter contains more saturated fat than corn oil, and is a solid at room temperature while corn oil is a liquid.

Phospholipids

Phospholipids have a structure like a triglyceride (see diagram above), but contain a phosphate group in place of the third fatty acid. The phosphate group is polar and therefore capable of interacting with water molecules.

Phospholipids spontaneously form a bilayer in a watery environment. They arrange themselves so that the polar heads are oriented toward the water and the fatty acid tails are oriented toward the inside of the bilayer (see the diagram below).

In general, nonpolar molecules do not interact with polar molecules. This can be seen when oil (nonpolar) is mixed with water (polar). Polar molecules interact with other polar molecules and ions. For example table salt (ionic) dissolves in water (polar).

The bilayer arrangement shown below enables the nonpolar fatty acid tails to remain together, avoiding the water. The polar phosphate groups are oriented toward the water.

Membranes that surround cells and surround many of the structures within cells are primarily phospholipid bilayers.

Steroids

Steroids have a backbone of 4 carbon rings.

Cholesterol (see diagram above) is the precursor of several other steroids, including several hormones. It is also an important component of cell membranes.

Saturated fats and cholesterol in the diet can lead to deposits of fatty materials on the linings of the blood vessels.

Waxes

Waxes are composed of a long-chain fatty acid bonded to a long-chain alcohol

They form protective coverings for plants and animals (plant surface, animal ears).

Proteins

Importance of proteins

Some important functions of proteins are listed below.

enzymes (chemical reactions)

hormones

storage (egg whites of birds, reptiles; seeds)

transport (hemoglobin)

contractile (muscle)

protective (antibodies)

membrane proteins (receptors, membrane transport, antigens)

structural

toxins (botulism, diphtheria)

Enzymes

Enzymes are proteins that speed up the rate of chemical reactions.

Example:

The presence of an enzyme in the chemical reaction diagrammed below causes hypothetical chemicals A and B to react, producing C.

Proteins are able to function as enzymes due to their shape. For example, enzyme molecules are shaped like the reactants, allowing the reactants to bind closely with the enzyme.

Amino Acids

Amino acids are the building blocks of proteins.

Twenty of the amino acids are used to make protein. Each has a carboxyl group (COOH) and an amino group (NH2).

Each amino acid is different and therefore has its own unique properties.

Some amino acids are hydrophobic, others hydrophilic. The carboxyl or amino group may ionize (forming NH3+ or COO-). The "R" group of some amino acids is nonpolar and the "R" group of some others is polar or it ionizes.

Amino acids are joined together by a peptide bond. It is formed as a result of a condensation reaction between the amino group of one amino acid and the carboxyl group of another.

Polypeptides

Two or more amino acids bonded together are called a peptide. A chain of many amino acids is referred to as a polypeptide. The complete product, either one or more chains of amino acids, is called a protein.

There is unequal sharing of electrons in a peptide bond. The O and the N are negative and the H is positive.

Levels of structure

The large number of charged atoms in a polypeptide chain facilitates hydrogen bonding within the molecule, causing it to fold into a specific 3-dimensional shape.

The 3-dimensional shape is important in the activity of a protein.

Primary Structure

Primary structure refers to the sequence of amino acids found in a protein. The following is the primary structure of one of the polypeptide chains of hemoglobin.

val his leu thr pro glu glu lys ser ala val thr ala leu tyr gly lys val asn val asp glu val gly gly glu ala leu gly arg leu leu val val tyr pro try thr gln arg phe phe glu ser phe gly asp leu ser thr pro asp ala val met gly asn pro lys val lys ala his gly lys lys val leu gly ala phe ser asp gly leu ala his leu asp asp leu lys gly thr phe ala thr leu ser gln leu his cys asp lys leu his val asp pro glu asn phe arg leu leu gly asn val leu val cys val leu ala his his phe gly lys glu phe thr pro pro val gln ala ala tyr gln lys val val ala gly val ala asp ala leu ala his lys tyr his

Secondary structure

The oxygen or nitrogen atoms of the peptide bond are capable of hydrogen- bonding with hydrogen atoms elsewhere on the molecule. This bonding produces two common kinds of shapes seen in protein molecules, coils (helices) and pleated sheets. The helices and pleated sheets are referred to as a proteins secondary structure.

Tertiary structure

Tertiary structure refers to the overall 3-dimensional shape of the polypeptide chain.

Hydrophobic interactions with water molecules are important in creating and stabilizing the structure of proteins. Hydrophobic (nonpolar) amino acids aggregate to produce areas of the protein that are out of contact with water molecules.

Hydrophilic (polar and ionized) amino acids form hydrogen bonds with water molecules due to the polar nature of the water molecule.

Hydrogen bonds and ionic bonds form between R groups to help shape the polypeptide chain.

Disulfide bonds are covalent bonds between sulfur atoms in the R groups of two different amino acids. These bonds are very important in maintaining the tertiary structure of some proteins.

The shape of a protein is typically described as being globular or fibrous. Globular proteins contain both coils and sheets.

Quaternary structure

Some proteins contain two or more polypeptide chains that associate to form a single protein. These proteins have quaternary structure. For example, hemoglobin contains four polypeptide chains.

Denaturation

Denaturation occurs when the normal bonding patterns are disturbed causing the shape of the protein to change. This can be caused by changes in temperature, pH, or salt concentration. For example, acid causes milk to curdle and heat (cooking) causes egg whites to coagulate because the proteins within them denature.

If the protein is not severely denatured, it may regain its normal structure.

Other Kinds of Proteins

Simple proteins contain only amino acids. Conjugated proteins contain other kinds of molecules. For example, glycoproteins contain carbohydrates, nucleoproteins contain nucleic acids, and lipoproteins contain lipids.

Nucleic acids

DNA

DNA (deoxyribonucleic acid) is the genetic material. An important function of DNA is top store information regarding the sequence of amino acids in each of the body’s proteins. This "list" of amino acid sequences is needed when proteins are synthesized. Before protein can be synthesized, the instructions in DNA must first be copied to another type of nucleic acid called messenger RNA.

Structure of DNA

Nucleic acids are composed of units called nucleotides, which are linked together to form a larger molecule. Each nucleotide contains a base, a sugar, and a phosphate group. The sugar is deoxyribose (DNA) or ribose (RNA). The bases of DNA are adenine, guanine, cytosine, and thymine. Notice that the carbon atoms in one of the nucleotides diagrammed below have been numbered.

The diagram below shows how nucleotides are joined together to form a "chain" of nucleotides.

DNA is composed of two strands in which the bases of one strand are hydrogen-bonded to the bases of the other. The sugar-phosphate groups form the outer part of the molecule while the bases are oriented to the center.

The strands are twisted forming a configuration that is often referred to as a double helix. The photograph below is of a model of DNA.

DNA.jpg (94691 bytes)

Complimentary base pairing

The adenine of one strand is always hydrogen-bonded to a thymine on the other. Similarly, Guanine is always paired with Cytosine.

A-T

G-C

Antiparallel

The end of a single strand that has the phosphate group is called the 5’ end. The other end is the 3’ end.

The two strands of a DNA molecule run in opposite directions. Note the 5’ and 3’ ends of each strand in the diagram.

RNA

RNA (ribonucleic acid) is similar to DNA and is involved in the synthesis of polypeptides and proteins as discussed above. The table below lists differences between DNA and RNA.

DNA

RNA

# Strands

2

1 (see diagram below)

Sugar

deoxyribose

ribose

Bases

A, T, G, C

A, U, G, C

RNA is single-stranded as shown below.

Codons

One strand of DNA (the anti-sense strand) is used as a template to produce a single strand of mRNA. The bases in the mRNA strand are opposite (complimentary) to the bases in the DNA template strand; it resembles the sense strand of DNA except that the base thymine is replaced by uracil. The mRNA contains three-letter (three-base) codes used to determine the sequence of amino acids in the polypeptide that it codes for. For example, in the diagram below, GUG is the code for valine. The sequence of codes in DNA therefore determines the sequence of amino acids in the protein.

Each three-letter code in mRNA is a codon. It is the code for one amino acid.

Click here for details on how information is stored in DNA.

ATP

ATP (adenosine triphosphate) is a nucleotide that is used in energetic reactions for temporary energy storage.

Energy is stored in the phosphate bonds of ATP. When ATP breaks down to form ADP and Pi, energy is released. Normally, cells use the energy stored in ATP by breaking one of the phosphate bonds, producing ADP. Energy is required to convert ADP + Pi back to ATP.

ATP is continually produced and consumed as illustrated below.

Review

Use the symbols below to draw a disaccharide, polysaccharide, triglyceride, phospholipid, polypeptide, and DNA. Use short, straight lines to represent covalent bonds.

Why is carbon such a special element?
Let's look at its chemistry in a little more detail.

Carbon (C) appears in the 2nd row of the periodic table and has atomic number of 6. Given our discussion of electron shells it is easy to see that carbon has 4 electrons in its valence shell. Since carbon needs 8 electrons to fill its valence shell, it forms 4 bonds with other atoms (each bond consisting of one of carbon's electrons and one of the bonding atom's). Every valence electron participates in bonding, thus a carbon atom's bonds will be distributed evenly over the atom's surface. These bonds form a tetrahedron, as illustrated below:

An organic molecule (hydrocarbon) is formed when carbon bonds to hydrogen. The simplest hydrocarbon consists of 4 hydrogen atoms bonded to a carbon atom (called methane):



In addition to binding to hydrogen, carbon can also bind to other carbon atoms, as illustrated below:


In fact the uniqueness of carbon comes from the fact that it can bind to itself. Carbon atoms can form long chains:


branched chains:


rings:


in fact, there appears to be almost no limit to the number of different structures that carbon can form. To add to the complexity of organic chemistry, neighboring carbon atoms can form double and triple bonds in addition to single carbon-carbon bonds:

Table I

A carbon-carbon single bond

A carbon-carbon double bond

A carbon-carbon triple bond
Keep in mind that each carbon atom forms 4 bonds. As you increase the number of bonds between carbon atoms, the number of hydrogen atoms in the molecule decreases (as can be seen in the table above).

Nomenclature (naming compounds):
The simplest hydrocarbons are those that contain only carbon and hydrogen. As we have seen, these come in three varieties: 1) alkanes, molecules with only single bonds, 2) alkenes, those with one or more double bond and 3) alkynes, those with one or more triple bond. Basic organic chemistry can be thought of as a molecular Erector Set, if you know the number of carbon atoms and the type of bonds in a molecule, you can build the molecular structure. To describe the number of carbon atoms in a hydrocarbon, chemists use prefixes in the molecule's name. The first 10 prefixes used in organic chemistry are shown below. To complete the hydrocarbon name, the prefix is attached to the ending of the root word (drop the alk- from the words alkane, alkene or alkyne) to describe the type of bonding on the molecule. The hydrocarbon names (also called nomenclature) is described in Table II using the first 10 alkanes as examples.

As we have discussed, each carbon atom has 4 bonds. As you add carbon to a molecule, the empty carbon bonds are filled with hydrogen atoms (or other elements, as we will soon see). You can calculate the number of H atoms in the simple alkanes. The number of H atoms in a simple alkane equals two times the number of carbon atoms plus 2, or (2n + 2), where n is the number of carbon atoms in the molecule. The simple alkenes have 1 double bond and 2 fewer H atoms in the molecule; the number of H atoms in the simple alkenes = (2n). Simple alkynes contain 1 triple bond 2 fewer H atoms than the alkene, or (2n - 2) H atoms.

The simple hydrocarbons are fairly common. Methane, for example, is released by decaying organic matter and is the main compound in natural gas. These chemicals are generally gases or liquids in nature and are very flammable. Butane is used in cigarette lighters. Ethyne, also known as acetylene, is used in welding.

In addition to carbon and hydrogen, hydrocarbons can also contain other elements. The alcohols, for example, are a group of hydrocarbons in which a hydroxol (-OH) group is bound to a carbon skeleton. These compounds are named like the simple hydrocarbons, a prefix attached to a root ending (-anol for the alcohols). Thus ethanol, is a 2 carbon alcohol with the structure:

Most people are familiar with this organic compound as it is the active ingredient in "alcoholic" beverages such as beer and wine.

While the simple hydrocarbons are important, they do not themselves commonly occur in living organisms (except for during the occasional bout of methane flatulence). The simple hydrocarbons are the building blocks of more complex molecules that make up living organisms. In the next lesson, we will introduce some of these molecules and their biochemistry, the chemistry of life.

Table II
 
 
ie.: Alkanes
Hydrocarbon prefix # of carbon atoms name formula     structure*
           Meth
1
methane CH4
           Eth
2
ethane C2H6
           Prop
3
propane C3H8
           But
4
butane C4H10
           Pent
5
pentane C5H12
           Hex
6
hexane C6H14
           Hept
7
heptane C7H16
           Oct
8
octane C8H18
           Non
9
nonane C9H20
           Dec
10
decane C10H22
Fossil Fuels - Crude Oil

1 Name the three Fossil Fuels.
2 What is the Original Source of Energy in Fossil Fuels?
3 Are Fossil Fuels a Finite Resource?
4 Are Fossil Fuels Renewable?
5 What has Crude Oil come from?
6 Under what Conditions has Crude Oil formed?
7 What is Natural Gas mostly made from?
8 Crude Oil is a mixture of mostly what type of Substance?
9 Describe the Fractional Distillation of Crude Oil.
10 Name the Fraction used as Fuel for Cars.
11 Name the Fraction used as Fuel for Aircraft.
12 Name the Fraction used as Fuel for Trains.
13 Name the Fraction used for a Road Surface.
14 Why is Cracking used?
15 What type of reaction is Cracking?
16 What Catalyst is used for Cracking?

Hydrocarbons - Alkanes

17 What is a Hydrocarbon?
18 How does the Boiling Point change as Hydrocarbons get Bigger?
19 How does the Flammability change as Hydrocarbons get Bigger?
20 Name the Alkane containing two Carbon Atoms.
21 Name the Alkane containing three Carbon Atoms.
22 Name the Alkane containing four Carbon Atoms.
23 What does Homologous mean?
24 What is the General Formula for an Alkane?
25 What are Alkanes?
26 Are Alkanes Saturated or Unsaturated?
27 Draw a Dot and Cross diagram for a Methane Molecule.
28 Draw the Structural Formula of a Methane Molecule.
29 Draw the Structural Formula of a Propane Molecule.
30 Draw the Structural Formula of a Butane Molecule.
31 Draw the Structural Formula of an Octane Molecule.
32 What are Alkanes mainly used as?

See also the section on Isomers below.

Hydrocarbons - Alkenes

33 What is the General Formula for an Alkene?
34 What are Alkenes?
35 Are Alkenes Saturated or Unsaturated?
36 Draw a Dot and Cross diagram for an Ethene Molecule.
37 Draw the Structural Formula of an Ethene Molecule.
38 Draw the Structural Formula of a Propene Molecule.
39 Draw the Structural Formula of a Butene Molecule.
40 Give one Use of an Alkene.
41 How can Bromine Water distinguish between an Alkene and an Alkane?
42 What is an Addition Reaction?
43 What is the Main Source of Alkenes?
See also the section on Isomers below.

Hydrocarbons - Cycloalkanes

44 What is the General Formula for a Cycloalkane?
45 Are Cycloalkanes Saturated or Unsaturated?
46 Draw the Structural Formula of a Cyclopropane Molecule.
47 Draw the Structural Formula of a Cyclobutane Molecule.
48 Draw the Structural Formula of a Cyclohexane Molecule.

Hydrocarbons - Isomers

49 What are Isomers?
50 Do Isomers have Different Physical Properties?
51 How many Isomers does Butane have?
52 Draw the Isomers of Butane.
53 Does a Straight Chain or a Branched Chain have a Higher Boiling Point?
54 What is the reason for the Higher Boiling Point?
55 Draw the Isomers of Pentane.
56 Does Changing the Shape of a Molecule produce a Different Isomer?
57 Does Changing the Position of a Double Bond produce a Different Isomer?
58 Draw the Isomers of Butene.
59 There are five Isomers of Pentene. How many can you draw?

Hydrocarbons - Combustion

60 What is a Combustion?
61 Is Combustion a form of Oxidation or Reduction?
62 Is Combustion Exothermic or Endothermic?
63 What does Excess of Air mean?
64 Write the Balanced Equation for the Complete Combustion of Methane.
65 What Colour is the Flame?
66 Write the Balanced Equation for the Complete Combustion of Ethane.
67 What does Incomplete Combustion mean?
68 What Colour is the Flame?
69 Write the Balanced Equation for the Incomplete Combustion of Methane.
70 What does Carbon Monoxide smell like?
71 How does Carbon Monoxide Poison you?

Alcohols (See also Ethanol below)

72 What is the General Formula for an Alcohol?
73 What does Homologous mean?
74 What is the Name of the Alcohol containing two Carbon Atoms?
75 What is the Name of the Alcohol containing three Carbon Atoms?
76 What is the Functional Group for Alcohols?
77 Is Cholesterol an Alcohol?
78 Draw the Structural Formula of a Methanol Molecule.
79 Draw the Structural Formula of an Ethanol Molecule.
80 Draw two Isomers of Propanol.
81 What is a Primary Alcohol?
82 What is a Secondary Alcohol?
83 What is a Tertiary Alcohol?
84 What is the Molecular Formula of Butanol?
85 There are four Isomers of Butanol. How many can you draw?
86 What is the Molecular Formula of Pentanol?
87 There are eight Isomers of Pentanol. How many can you draw?
88 Which Gas is produced when Sodium is added to an Alcohol?
89 Write the Balanced Equation for the Reaction between Sodium and Methanol.
90 Write the Balanced Equation for the Reaction between Sodium and Propanol.
91 Write the Balanced Equation for the Combustion of Methanol.
92 Write the Balanced Equation for the Combustion of Propanol.

See also the Reaction between Alcohols and Carboxylic Acids.

Alcohols - Ethanol

93 What is the Molecular Formula of Ethanol?
94 Is Ethanol a Hydrocarbon?
95 Is Ethanol acidic, neutral or Alkaline?
96 Write the Balanced Equation for the Reaction between Ethene and Steam.
97 What Catalyst is used for the Reaction between Ethene and Steam?
98 What is a Continuous Process?
99 Write the Word Equation for the Fermentation of Glucose.
100 Why must Fermentation be carried out in the Absence of Air?
101 Why does Fermentation Stop when Alcohol concentration reaches about 10%?
102 What is a Batch Process?

Ethanol can be made by a Batch Process or a Continuous Process.

103 1. Which Process uses a Renewable Resource?
104 2. Which Process has the Fastest Rate of Reaction?
105 3. Which Process make a Pure Product?
106 4. Which Process does Industry Prefer?
107 Give two Uses of Ethanol.
108 Write the Balanced Equation for the Complete Combustion of Ethanol.
109 What is added to Methylated Spirits to make it Poisonous to Drink?
110 Give one Use of Methylated Spirits.
111 Was is the Product of the Dehydration of Ethanol?
112 What Catalyst is used for the Dehydration of Ethanol?

Carboxylic Acids (See also Ethanoic Acid below)

113 What is the General Formula for a Carboxylic Acid?
114 What does Homologous mean?
115 Are Carboxylic Acids Weak or Strong?
116 What is the Name of the Carboxylic Acid containing two Carbon Atoms?
117 What is the Name of the Carboxylic Acid containing three Carbon Atoms?
118 What is the Functional Group for Carboxylic Acids?
119 Is Aspirin a Carboxylic Acid?
120 Is Vitamin C a Carboxylic Acid?
121 Draw the Structural Formula of Methanoic Acid.
122 Draw the Structural Formula of Propanoic Acid.
123 What type of Reaction is Methanoic Acid plus Sodium Hydroxide?
124 Write the Balanced Equation for Methanoic Acid plus Sodium Hydroxide.
125 Write the Balanced Equation for Butanoic Acid plus Zinc Carbonate.
126 Write the Balanced Equation for Zinc plus Propanoic Acid.
127 How do you make an Ester?
128 What Catalyst is used when you make an Ester?
129 Give two Uses of Esters.
130 Write the Balanced Equation for Methanoic Acid plus Methanol.
131 Write the Balanced Equation for Methanoic Acid plus Propanol.
132 Write the Balanced Equation for Methanoic Acid plus Butanol.
133 Write the Balanced Equation for Propanoic Acid plus Methanol.
134 Write the Balanced Equation for Propanoic Acid plus Ethanol.
135 Write the Balanced Equation for Propanoic Acid plus Butanol.
136 Write the Balanced Equation for Butanoic Acid plus Methanol.
137 Write the Balanced Equation for Butanoic Acid plus Propanol.
138 Write the Balanced Equation for Butanoic Acid plus Butanol.

Carboxylic Acids - Ethanoic Acid

139 What is the Molecular Formula of Ethanoic Acid?
140 Is Ethanoic Acid a Weak or Strong Acid?
141 Is Ethanoic Acid found in Vinegar?
142 Write the Balanced Equation for the Reaction between Ethanol and Oxygen.
143 Draw the Structural Formula of Ethanoic Acid.
144 Which Polymer is Ethanoic Acid used to make?
145 Write the Balanced Equation for Ethanoic Acid plus Methanol.
146 Write the Balanced Equation for Ethanoic Acid plus Ethanol.
147 Write the Balanced Equation for Ethanoic Acid plus Propanol.
148 Write the Balanced Equation for Ethanoic Acid plus Butanol.

Polymers

149 What is a Polymer?
150 What is a Monomer?
151 What is Polymerisation?
152 Give two Conditions used for Polymerisation.
153 Describe the Polymerisation of Ethene.
154 Draw the Repeat Unit for Poly(ethene).
155 What is an Addition Polymer?
156 What is Another Name for Poly(chloroethene)?
157 What is Another Name for Poly(phenylethene)?
158 Describe the Structure of a Thermosoftening Polymer.
159 Is Poly(ethene) a Thermosoftening Polymer?
160 Is Poly Vinyl Chloride a Thermosoftening Polymer?
161 Are Epoxy Resins Thermosoftening Polymers?
162 Describe the Structure of a Thermosetting Polymer.
163 Is Melamine a Thermosetting Polymer?
164 Is Bakelite a Thermosetting Polymer?
165 Is Poly(styrene) a Thermosetting Polymer?
166 Give two Uses of Poly(ethene).
167 Give two Uses of Poly(propene).
168 Give one Use of Poly(styrene).
169 Give one Use of Poly Vinyl Chloride.
170 Are Polymers Biodegradable?
171 What does Biodegradable mean?
172 Name two Pollutants caused by Burning Polymers.

Environmental Issues

173 Give one Example of Pollution caused by Extraction or Transport of Oil.
174 What Problem is caused by adding Carbon Dioxide to the Atmosphere?
175 What is Global Warming?
176 What Effects might Global Warming have?
177 What Evidence is there that Global Warming is Really Happening?
178 Why are some Gases called Greenhouse Gases?
179 Give two Examples of Greenhouse Gases.
180 Why is Natural Rain slightly Acidic?
181 How does Sulfur in Fossil Fuels cause Acid Rain?
182 Give two Harmful Effects of Acid Rain.
183 How can Soils or Lakes be made less Acidic?
184 How can High Temperature Combustion of Fossil Fuels add to Acid Rain?
185 Give two Alternative Energy Resources to Fossil Fuels.