How to Get Dissertation Help Via the Internet

Dissertation or Thesis is one of the biggest hurdles that college and university students have to face during their education. It is very important in earning a graduation or a post-graduation degree.

It is very significant because the Dissertation or Thesis will have to be prepared in the most unique way, with a unique subject or topic or sub-topic, etc. The preparation of the dissertation or thesis is dependant upon the student’s understanding of the concerned subject or the sub-topic. Lot of research into the subject is required by the student. This is critical in obtaining a post-graduation degree.

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• Dissertation Topic Ideation: Selecting a topic for dissertation is very important. HelpWithThesis.com experts help you by brainstorming and suggest a topic that can be worked on.
• Dissertation Proposal: Dissertation Proposal is the second step in the preparation of Dissertation. A dissertation proposal has to be submitted to the panel which views the dissertations. This panel will approve the dissertation on the particular topic only after which the dissertation work can begin.
• Experiments: After the Dissertation Proposal, comes the stage of actual experimentation or analysis of the given data. This experimentation and analysis will give out results which are used to compare with the proposed results.
• Based on the conclusion, the student shall prepare a conclusion where the differences in actual and theoretical results is discussed.
• The last stage is the final report making. This report contains all the details from the starting of the dissertation to the ending ie the conclusion of the dissertation or thesis is given.

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Material Science in Chemical Engineering from HelpWithAssignment.com

Material Science in Chemical Engineering

Life in the 21^st century is every dependant on an unlimited variety of advanced materials. In our consumptive world, it is easy to take for granted the macro, micro and nanoscopic building blocks that comprise many any item ever produced. We are spoiled by the technology that adds convenience to our lives, such as microwave ovens, laptop computers, digital cell phones and improved modes of transportation. However, we rarely take time to think about and appreciate the materials that constitute these modern engineering feats.

The term material may be broadly defined as any solid-state component or device that may be used to address a current or future societal need. For instance, simple building materials such as nails, wood, coatings, etc address our need for shelter. Other more intangible materials such as nanodevices may not yet be widely proven for particular applications, but will be essential for the future needs of our civilization. Although the above definition includes solid nanostructural building blocks that assemble to form larger materials, it excludes complex liquid compounds such as crude oil, which may be more properly considered a precursor for materials.

There is a sharp distinction between the various classes of materials that we see today. For example: a thin film is defined as having a film of thickness less than 1μm; however, if the thickness drops below 100nm, the dimensions may be more accurately classified within the nanoscale regime. Likewise, liquid crystals are best described as having properties intermediate between amorphous and crystalline phases, and hybrid composite materials involve both inorganic and organic components.

The broadly defined discipline of materials chemistry is focused on understanding the relationships between the arrangements of atoms, ions, or molecules comprising a material and its overall bulk structural/physical properties. By this designation, common disciplines such as polymer, solid-state and surface chemistry would all be placed within the scope of materials chemistry. This broad field consists of studying the structures/properties of existing materials, synthesizing and characterizing new materials and its overall bulk structural/physical properties. By this designation, common disciples such as polymer, solid-state and surface chemistry would all be placed within the scope of materials chemistry. This broad field consists of studying the structures/properties of existing materials, synthesizing and characterizing new materials and using advanced computational techniques to predict structures and properties of materials that have not yet been realized.

Although the study of materials chemistry is a relatively new entry in chemistry, it has always been an important part of chemistry. By most accounts, Neolithic man (10000 – 300) BC was the first to realize that certain materials such as limestone, wood, shells and clay were most easily shaped into materials used as utensils, tools and weaponry.

Applications for metallic materials date back to the Chalcolithic age (4000 – 1500) BC where copper was used for a variety of uses.

Metal alloys were first used in the Bronze age (1400 – 0) BC, where discovery that doping copper with other compounds drastically altered the physical properties of the material.

The Iron age (1000 - 1950) AD first brought about applications for iron based materials. Since the earth’s crust contains significantly more iron than copper, the latter was abandoned for material applications.

Although building and structural materials such as ceramics, glasses and asphalt have not dramatically changed since their invention, the world of electronics has undergone rapid changes. Many new architectures for advanced material design are surely yet undiscovered, as scientists are now attempting to mimic the profound structural order existing in living creatures and plant life, which is evident as one delves into their microscopic regimes.

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Electrical Engineering Electrical Networks from HelpWithAssignment.com

Electrical Engineering Electrical Networks

Electrical circuits may consist of one or more sources of energy and number of electrical parameters, connected in different ways. The different electrical parameters or elements are resistors, capacitors and inductors. The combination of such elements along with various sources of energy gives rise to complicated electrical circuits, generally referred to as electrical networks. The terms circuit and network are used synonymously in the electrical literature. The dc circuits consist of only resistances and dc sources of energy. And the circuit analysis means to find a current through or voltage across any branch of the circuit.

What is a network?

Any arrangement of the various electrical energy sources along with the different circuit elements is called an electrical network.

Network Element

Any individual circuit element with two terminals which can be connected to other circuit element is called a network element.

Network elements can be either active elements or passive elements. Active elements are the elements which supply power or energy to the network. Voltage source and current source are the examples of active elements. Passive elements are the elements which either store energy or dissipate energy in the form of heat. Resistor, inductor and capacitor are the three basic passive elements. Inductors and capacitors can store energy and resistors dissipate energy in the form of heat.

Branch

A part of the network which connects the various parts of the network with one another is called a branch. A branch may consist of more than one element.

Junction point

A point where three or more branches meet is called a junction point.

Node

A point at which two or more elements are joined together is called a node. The junction points are also the nodes of the network.

Mesh or loop

Mesh or a loop is a set of branches forming a closed path in a network in such a way that if one branch is removed then the remaining branches do not form a closed path. A loop also can be defined as a closed path which originates from a particular node, terminating at the same node, travelling through various other nodes, without travelling through any node twice.

Classification of networks

The behavior of the entire network depends on the behavior and characteristics of the elements. Based on such characteristics electrical networks can be classified as

Linear Network: A circuit or network whose parameters ie elements like resistances, inductances and capacitances are always constant irrespective of the change in time, voltage and temperature, etc is known as linear network. The Ohm’s law can be applied to such a network.

Nonlinear network: A circuit whose parameters change their values with change in time, temperature, voltage, etc is known as non-linear network. The Ohm’s law may not be applied to such network. Such network does not follow the law of superposition. The response of the various elements is not linear with respect to their excitation. The best example is a circuit consisting of a diode where diode current does not vary linearly with the voltage applied to it.

Bilateral network: A circuit whose characteristics, behavior is same irrespective of the direction of current through various elements of it, is called bilateral network. Network consisting only resistances is good example of bilateral network.

Unilateral Network: A circuit whose operation, behavior is dependant on the direction of the current through various elements is called unilateral network. Circuit consisting diodes, which allows flow of current only in one direction is good example of unilateral circuit.

Active network: A circuit which contains at least one source of energy is called active. An energy source may be a voltage or current source.

Passive networks: A circuit which contains no energy source is called passive circuit.

Lumped network: A network in which all the network elements are physically separable is known as lumped network.

Distributed network: A network in which the circuit elements like resistance, inductance, etc cannot be physically separable for analysis purposes, is called distributed network. The best example of such a network is a transmission line where resistance, inductance, and capacitance of transmission line are distributed all along its length and cannot be shown as separate elements anywhere in the circuit.

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Electrical Engineering Circuit Laws at HelpWithAssignment.com

Electrical Engineering Circuit Laws

Circuit laws

Two important laws are based on the physical properties of electric charges and these laws form the foundation of circuit analysis. They are Kirchhoff’s current law and Kirchhoff’s voltage law. While Kirchhoff’s Current Law (KCL) is based on the principle of conservation of electric charge, Kirchhoff’s Voltage Law (KVL) is based on the principle of energy conservation.

Kirchhoff’s Current Law

At any instant, the algebraic sum of the currents i entering a node in a circuit is equal to zero. The application of KCL at node C yields the following equation:

i₁+ i₂+ i₃ = 0

similarly at node D, KCL yields:

i₁ - i₂- i₃ = 0

Kirchhoff’s Voltage Law

At any instant, the algebraic sum of the voltages (v) around a loop is equal to zero. In going around a loop, a useful convention is to take the voltage drop (going from positive to negative) as positive and the voltage rise (going from negative to positive) as negative.

Circuit Analysis

Analysis of an electrical circuit involves the determination of voltages and currents in various elements, given the element values and their interconnections. In a linear circuit, the v-i relations of the circuit elements and the equations generated by the application of KCL at the nodes and of KVL for the loops generate a sufficient number of simultaneous linear equations that can be solved for unknown voltages and currents. Various steps involved in the analysis of linear circuits are as follows.

For all the elements except the current sources, assign a current variable with arbitrary polarity. For the current sources, current values and polarities are given.

For all the elements except the voltage sources, assign a voltage variable with polarities based on the passive sign convention. For voltage sources, the voltages and their polarities are known.

Write KCL equations at N-1 nodes, where N is the total number of nodes in the circuit.

Write expressions for voltage variables of passive elements using their v-i relations.

Apply KVL equations for E-N+1 independent loops, where E is the number of elements in the circuit. In the case of planar circuits, which can be drawn on a plane paper without edges crossing over one another, the meshes will form a set of independent loops. For non-planar circuits, use special methods that employ topological techniques to find independent loops.

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Electrical Engineering at HelpWithAssignmentcom

Electrical Engineering

Electric Charge

The International System Unit of charge: C (Coulomb)

Electricity is based upon the existence of electric charges, which are positive and negative. A force exists between electric charges, which is described by Coulomb’s law. Like charges repel each other and unlike charges attract each other.

From the physical point of view, every charge is a multiple of the elementary charge e.

Elementary charge e ­ ±1.602 × 10^-19 Coulomb

Electrons carry a negative charge and Protons carry a positive charge. A lack of electrons in a body means the body is positively charged. Similarly, an excess of electrons means it is negatively charged.

Electric Current

The international Systems Unit of Current: A (Ampere)

The directed motion of electric charge carriers is called an electric current.

I = dQ/dt

The electric current I in a conductor is the charge dQ passing through the conductor cross-sectional area during the time interval dt. The current is a direct current if the charge passing the conductor per time interval is constant.

DC current: I = dQ/dt = constant

Technical direction of current:

The positive current direction is the motion of the positive charge carriers. This is equivalent to the opposite motion of negative charge carriers. In metal conductors electrons are the charge carriers. From the physical point of view, the electrons therefore move opposite the positive current flow.

Electric charges always move in a closed loop. This means:

The electric current always flows in a closed circuit.

Voltage and Potential

The International Systems unit of Voltage: V (Volt)

The electric voltage is the force that causes the movement of the charge carriers.

The electric current always flows from the positive terminal to the negative terminal of the voltage source. Since the current flows in a closed loop, inside the voltage source the current flows from the negative to the positive terminal.

The potential φ is a scalar quantity. Given that one point in space has the potential φ = 0, then all the other points in space can be assigned an absolute potential. This potential is obtained from the energy that has to be provided to move the elementary charge from the point with φ = 0 to the given point. In this physical model, the voltage V is the difference between two potentials. For this reason voltage is often referred to as potential difference.

V₂₁ = φ₂ – φ₁

Ohm’s Law

The current flowing through a load is dependant on the driving voltage. Provided the properties of the load are independent of the current flowing through it and the voltage applied to it.

The current changes proportionately with the voltage. The constant R relating current and voltage is called electric resistance.

Resistance and Conductance

SI unit of resistance is Ω (Ohm), 1Ω = 1 V/A

SI Unit of conductance: S (Siemens), 1S = 1 A/V

The relationship between current and voltage is described by the quantities resistance R and conductance G.

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Bonus Shares Vs Stock Splits In Financial Management from HelpwithAssignment.com

Bonus Shares Vs Stock Splits In Financial Management

Definition: Bonus Shares are those shares which are issued to shareholders’ by a healthy company without any cost. These Bonus Shares are issued in proportion to the existing shares a shareholder has as a result of capitalization of reserves.

In the wake of a Bonus Issue:

· In this case the Shareholders’ proportional ownership remains unchanged.

· The book value per share, the earnings per share and the market price per share decrease but the number of shares increased.

Here is an illustration given on The Effects of Bonus Shares on the Equity proportions of the Balance Sheet.

Part A: Equity Portion before Bonus Issue
Paid-up Share Capital	$10000000
100000 shares of $10 each fully paid
Reserves and Surplus	$30000000
Part B: Equity Portion after bonus issue in the ratio 2:1
Paid-up Share Capital 200000 shares of $10 each fully paid	$20000000
Reserves and Surplus	$20000000

Few reasons are discussed for Issuing of Bonus Shares:

· The Bonus issue may likely to bring the market price per share within a more popular range.

· It increases the number of outstanding shares which involves in promoting more active trading. The normal rate of dividend may likely to decline.

· The share capital base increases and the company may achieve a more respectable place in the eyes of the investing community.

· Shareholders regard a Bonus issue as a firm indication that the prospects of the company have brightened and they can reasonably look for an increase in total dividends.

· This can improve the prospects of raising additional funds. In recent years many firms have issued bonus shares that are prior to the issue of convertible debentures.

Definition: An increase in the number of outstanding shares of a company’s stock, such proportionate equity of shareholders remains same. This requires approval from the Board of Directors and the Shareholders. A Corporation, whose stock is performing good may, chooses to split its shares and distributing additional shares to existing Shareholders’. In a stock split the par value per share is reduced and the number of shares is increased proportionately.

An illustration to exhibit the nature of these change effects of a Stock Split on the Equity Proportions of a balance Sheet:

Part A: Equity Portion Before Stock Split
Paid-up Share Capital 100000 shares of $50, each fully paid	$5000000
Reserves and Surplus	$10000000
Part B: Equity Portion after Stock Split in the ratio of 5:1
Paid-up Share Capital 500000 shares of $10, each fully paid	$5000000
Reserves and Surplus	$10000000

Comparison of Bonus Shares and Stock Splits:

Bonus Issue	Stock Splits
The Par Value of the share is unchanged	The Par Value of the share is reduced
A part of reserves is Capitalized	There is no Capitalization of reserves
The Shareholders’ Proportional ownership remains unchanged.	The Shareholders’ Proportional ownership remains unchanged.
The book value per share, earnings per share and the market price per share decline.	The book value per share, earnings per share and the market price per share decline.
The market price per share is brought within a more popular trading range.	The market price per share is brought within a more popular trading range.

Here we can see a Stock Split is similar to the Bonus Issue from the economics point of view, although there are some differences in accounting point of view.

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This article is in continuation with our previous articles on Finance that include Private Capital and Venture Capital, Mergers & Acquisitions, CAPM Model, Capital Structure

Bernoulli’s Theorem in Chemical Engineering from HelpWithAssignment.com

Bernoulli’s Theorem in Chemical Engineering

Bernoulli’s Theorem in fluid dynamics is one of the important discoveries. The relation among pressure, velocity and elevation in a moving fluid, the compressibility and viscosity of which are negligible and the flow of which is steady or laminar. The Theorem was first derived in 1738 by Swiss mathematician Daniel Bernoulli. The theorem states that, in effect, that the total mechanical energy of the flowing fluid, comprising the energy associated with fluid pressure, the gravitational potential energy of elevation and the kinetic energy of fluid motion, remains constant. Bernoulli’s theorem is the principle of energy conservation for ideal fluids in steady or streamline flow.

Bernoulli’s principle can be applied to various types of fluid flow. There are different applications of Bernoulli’s Theorem. The theorem can be derived through the law of conservation of energy. This states that, in a steady flow, the sum of all forms of mechanical energy in a fluid along a streamline is the same at all points on that streamline. This requires that the sum of kinetic energy and potential energy remain constant. Thus an increase in the speed of the fluid occurs proportionately with an increase in both its dynamic pressure and kinetic energy and a decrease in its static pressure and potential energy. If the fluid is flowing out of a reservoir the sum of all forms of energy is the same on all the streamlines because in a reservoir the energy per unit mass is the same everywhere.

Fluid particles are subject only to pressure and their own weight. If a fluid is flowing horizontally and along a section of a streamline, where the speed increases it can occur only because the fluid on that section has moved from a region of a higher pressure to a region of lower pressure and it its speed decreases, it can only occur because it has moved from a region of lower pressure to a region of higher pressure. Consequently, within a fluid flowing horizontally, the highest speed occurs where the pressure is lowest, and the lowest speed occurs where the pressure is highest.

In most liquid flows and gas flows at high speeds, the mass density of a fluid parcel can be considered to be constant, regardless, of pressure variations in the flow. For this reason the fluid in such flows can be considered to be incompressible and these flows can be described as incompressible flow. Bernoulli performed experiments on liquids and his equation in its original form is valid only in incompressible flow. A common form of Bernoulli’s equation, valid at any arbitrary point along a streamline where gravity is constant, is:

V²/2 + gz + p/ρ = constant

Where,

v is the fluid flow speed at a point on a streamline

g is the acceleration due to gravity

z is the elevation of the point above a reference plane, with the positive z-direction pointing upward – so in the direction opposite to the gravitational acceleration

p is the pressure of the fluid at all the points in the fluid

ρ is the density of the fluid at all points in the fluid

For conservative force fields, Bernoulli’s equation can be generalized as

V²/2 + Ψ + p/ρ = constant

Where, Ψ is the force potential at the point considered on the streamline.

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Chemical Engineering Heat Transfer from HelpWithAssignment.com

Chemical Engineering Heat Transfer

The field of heat transfer explores the rate at which heat flows from a region of high temperature to one of low temperature. Heat flow occurs as molecules transfer their thermal energy, in the form of molecular motion, to nearby lower energy molecules or by fast moving molecules moving to another region of the system. The mechanisms of heat transfer can be categorized as occurring by convection, conduction, or radioactive processes. Convection occurs in a liquid or gas as high energy, fast moving molecules create an area of low density media that rises relative to the slower moving, denser regions. This molecular movement redistributes the energy in a system. This type of heat transfer is how heated air from a register moves around a room to reach a pleasant 22°C (72°F) during the winter. Conduction occurs as high energy molecules collide with lower energy molecules thereby transferring some of their kinetic energy to their collision partner. Conduction transfers the thermal energy around more evenly, allowing heat to travel from warmer to cooler regions. Conductive heating is used in electric stoves to heat pans for cooking. Radioactive heat transfer occurs when a warm object emits electromagnetic radiation. The radiation can be used to heat an object at a distance from the heat source.

The amount of heat transferred through by conduction is expressed by

Q/t = -kS (T1 – T2/ d)

Where Q is the amount of heat transferred, t is the time taken, k is the conductivity of the material, S is the surface area through which the heat is transferred, d is the distance between the two ends of the system, T1 is the temperature at the higher temperature end and T2 is the temperature at lower temperature end.

These mechanisms tell about how heat travels in systems, but rate of transfer is also important. The most common way to describe the heat transfer rate is through the use of thermal-conductivity coefficients, which define how quickly heat will travel per unit of length (or area for convection processes). Every material has a characteristic thermal conductivity coefficient. Metals have high thermal conductivity, while polymers generally exhibit low thermal conductivities. One interesting application of thermal conductivity is the utilization of calcium carbonate in blown film processing. Calcium carbonate is added to a polyethylene resin to increase the heat transfer rate from the melt to the air surrounding the bottle. Without calcium carbonate, the resin cools much more slowly and production rates are decreased.

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Distillation in Chemical Engineering from HelpWithAssignment.com

Distillation

Distillation is the process of separation of volatile liquid from non-volatile substance or more frequently, the separation of two or more liquids in different volatility. If only one component of a mixture is volatile, there is no difficulty in obtaining it in a pure state by distillation and in many cases the constituents of a mixture of two or more volatile liquids may be separated – though frequently at much cost of time and materials.

Quantitative Analysis by Distillation: The determination by ordinary analytical methods of the relative quantities of two or more organic compounds in a mixture is often a matter of great difficulty, but in many cases, the composition of the mixture may be ascertained approximately and not seldom, with considerable accuracy from the results of a single distillation, if a very efficient still head is employed.

Difficulties encountered: The subject of fractional distillation is full of interest owing to the fact that difficulties so frequently occur, not only in the experimental work, but also in interpreting the results obtained.

In the distillation of petroleum, with the object of separating pure substances, such difficulties are of common occurrence and are due to one or other of three causes:- A. to the presence of two substances, the boiling point of which are very close together, B. to the presence of one or more components in relatively very small quantity, C. to the formation of mixtures of constant boiling point.

The separation of two liquids which boil at temperatures even 20° or 30° apart, such as ethyl alcohol and water, or benzene and isobutyl alcohol, may be impossible owing to the formation of a mixture of minimum or less frequently, of maximum boiling point. It is indeed, only in the case of substances which are chemically closely related to each other that the statement can be definitely made that the difficulty of separating the components of a mixture diminishes as the difference between their boiling points increases.

In any other case, we must consider the relation between the boiling points, or the vapor pressures, of mixtures of the substances and their composition and unless something is known of the form of the curve representing one or other of these relations, it is impossible to predict whether the separation will be an easy one or indeed, whether it will be possible.

The form of these curves depends largely on the chemical relationship of the components and it is now possible in a moderate number of cases, to form an estimate, from the chemical constitution of the substances, of the extent to which the curves would deviate from the normal form, and therefore to predict the behavior of a mixture on distillation.

Fractional distillation: Fractional distillation is frequently a very tedious process and there is necessarily considerable loss of material by evaporation and by repeated transference from the receivers to the still, but a great amount of both time and material may be saved by the use of a very efficient still-head and when the object of the distillation is to ascertain the composition of a mixture, very much greater accuracy is thereby attained.

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Electrochemsitry in Chemical Engineering from HelpWithAssignment.com

Electrochemsitry

In solid crystals such as NaCl, electrical charges are localized on those sites that form the lattice. These lattice sites are occupied not by neutral atoms, but by negatively charged chlorine or positively charged sodium ions and the crystal is held together by the columbic forces that exist between all electrically oppositely charged species. The energy of interaction between two particles of charge q1 and q2 at a distance r from one another is given by

U₁₂ = q₁-q₂/ 4πε_rε₀r

Where ε_r is the relative permittivity of the medium and ε₀ the permittivity of free space. The energy is positive when q1 and q2 have opposite signs. The corresponding force between the two particles is a vector quantity, directed along the inter-particle axis, r, if the two charges have the same sign, the force F is repulsive.

These coulombic forces are very powerful and ions are drawn close together before short-range repulsive forces come into play and an equilibrium interionic distance is established. The result that very large amounts of energy are needed to break down the lattice, leading, for example, to the familiar observation of high melting points in ionic crystals. The actual calculation of the energy required completely to break up the crystal lattice can be carried out provided some analytical form for the ionic repulsion can be written down. Commonly, this repulsion is deemed to take the form R12 = B/rⁿ, where B depends on the relative extension of valence and core-electron clouds.

The ability of an electrolyte solution to sustain the passage of electrical current depends on the mobility of its constituent charged ions in the electric field between electrodes immersed in the solution. Ions of charge ze₀, accelerated by the electric field strength, E, are subject to a frictional force, F, that increases with velocity, v, and is given, for simple spherical ions of radius r₁, by the Strokes formula, F = 6πnr_iv, where n is the viscosity of the medium. The result is that after a short induction period, the velocity attains a limited value, v_max, corresponding to the exact balance between the electrical and frictional forces.

Ze₀|E| = 6πnr₁v_max

And the terminal velocity is given by

It follows that for given values of n and |E|, each type of ion will have a transport velocity dependant on the charge and the radius of the solvated ion and a direction of migration dependant on the sign of the charge.

V_max = ze₀|E|/ 6πnr₁

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Organic Chemistry from HelpWithAssignment.com

Organic Chemistry

Organic Chemistry is the chemistry of the compounds of carbon. Although the fundamental laws and theories of chemistry are as applicable to these compounds as to all others, there are several reasons for their separate treatment.

In the first place, the number of compounds that contain carbon is extraordinarily large. The only other elements that enter into the composition of any very large number of substances are hydrogen and oxygen. Hydrogen and oxygen are also quite usually associated with carbon in organic compounds. This association, however, is of such nature that carbon is the dominant element. The sheer number of compounds that constitute carbon itself is a sufficient ground for making it a separate branch altogether.

There are certain general characteristics which distinguish the organic substances from the inorganic. Most of the compounds of carbon are decomposed at temperatures which are below a red heat, while many inorganic compounds withstand much higher temperatures and organic compounds are more liable to change when exposed to the light and air than are the inorganic.

The majority of organic substances are practically insoluble in water, which is the solvent of so many inorganic compounds, and are usually soluble in liquids such as ether, chloroform, alcohol, carbon disulphide, and benzene in which few of the inorganic compounds dissolve.

A complete discussion of the compounds of carbon would include carbon monoxide, carbon dioxide, carbon disulphide, certain carbides, carbonic acid and the carbonates – substances which are usually, treated in inorganic chemistry on account of their close relations to inorganic compounds.

All of these compounds, however, have also certain relations, to other compounds of carbon, so that some reference to them which will bring out this relation should be made in organic chemistry.

Sources of organic compounds: Carbon combines directly with hydrogen at high temperatures, and the hydrocarbons which are formed may be employed as the starting point for the preparation of a great variety of other organic compounds. Some simple organic substances may be made by the use of the oxides of carbon, its sulphide, chloride and one or two carbides of the metals, and these may then be built up into more complex compounds by laboratory methods. But in actual practice the chief sources of organic compounds are in the products elaborated in plants and animals.

These substances were the first to receive the name “organic”, and for a long time it was believed impossible to produce any of them artificially from the elements or from inorganic compounds.

Among the important organic compounds which are found already formed in plants are starch, cellulose, sugars, acids or salts of acids, such as oxalic, citric, tartaric acids, the alkoliods, such as quinine and strychnine and many other substances of greater or less complexity.

Petroleum contains many compounds of carbon and hydrogen. Many organic substances are also produced by the destructive distillation of coal, wood and bones – those which are contained in the coal tar being of the greatest interest and practical value.

Furthermore, fermentative processes produce ordinary alcohol from sugar, acetic acid from alcohol and a number of other compounds.

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This article is in continuation with our previous articles on Chemistry such as Classification and Types of Matter, Periodic Table, Structure of Atoms and Subatomic Particles