1.1 Chemistry and its Branches
Why does a cake rise in the oven?
What are fireworks made from?
How does my stomach digest food?
How does gasoline make an engine run?
What is the proper way to describe hot and cold?
What creates the shape of a snowflake?
Why does iron rust?
How can soot and diamond be so
different in appearance yet so chemically similar?
What makes propane such an efficient, clean-burning fuel?
These questions and many more are answered with chemistry. Chemistry has the power to explain innumerable phenomena in the world, from the ordinary to the bizarre. Understanding chemistry is the key to understanding the world as we know it. Chemistry is the study of the make-up of all things and how they behave.
Chemistry deals with chemical elements and compounds, which consist of atoms and molecules, and the reactions between them.
Everything we hear, see, smell, taste, and touch involves
chemistry and chemicals (matter). And hearing, seeing, tasting, and touching
all involves intricate series of chemical reactions and interactions in our
body. With such an enormous range of topics, it is essential to know about
chemistry at some level to understand the world around us.
Chemistry is sometimes called “THE CENTRAL SCIENCE,” because it bridges physics with other natural sciences, such as geology and biology.
Matter; Anything having mass and volume
Mass; the quantity of matter contained in a body
Volume; space occupied by body (quantification of how much
space an object occupies)
Space; The free area between two material objects
Everything that is anything is matter. Matter is defined as anything that has mass and takes up space. You are matter; trees, houses, rocks, water and even the air you breathe are matter.
Not everything that is a noun is matter, however.
Time, dreams, heat or light are not matter. They do not have any mass and they
do not take up space. They are not made of matter.
Origin of Word Chemistry
The word chemistry is derived from the word “Kheem”,
an old name of Egypt due to black colour of Egyptian soil.
But some experts believed that the word chemistry came from
the word “Chyma” meaning melt or cast.
As the time passed on the word changed to Al-kimyain in Arabic and then to “Chemistry” in English.
Branches of Chemistry
The chemistry has been divided into following nine main branches:
 | |
Physical
chemistry is the branch of chemistry which deals with relationship between
composition and physical properties of matter with the changes in them. It is
the branch of chemistry that deals with the physical properties of substances and their dependence on chemical bonding. It deals
with the forces and laws and principles governing the combination of atoms and molecules. It
is especially concerned with energy changes in physical and chemical processes.
It deals with the discovery and description of the theoretical basis of the behaviour of chemical substances. It is defined as dealing with the relations between the physical properties of substances and their chemical formations along with their changes.
It provides a basis
for every bit of chemistry including organic, inorganic, and analytical.
important areas of study include chemical thermodynamics, chemical kinetics, quantum chemistry, statistical mechanics, and spectroscopy. other branches of this subject are treated in the articles chemical action; energetics; solution; alloys; thermochemistry
This branch of chemistry deals with substances not containing carbon and that are not organic. Examples of such substances are minerals found in the earth's crust and non-living matter. Inorganic chemistry is the study of the properties and reactions of chemical elements and inorganic compounds (with the exception of carbon compounds).
[The detailed study of carbon compounds (or organic compounds) especially carbon-hydrogen compounds (hydrocarbons) and their derivatives are avoided in inorganic chemistry. However some carbon compounds like metal carbonates (CO32¯), bicarbonates (HCO3¯), cyanides (CN¯), thiocyanates (CNS¯), cyanates (CNO¯), carbides (C4¯), and oxides of carbon (CO and CO2) are studied in inorganic chemistry].
Organic chemistry is the branch of chemistry which deals with hydrocarbons and their derivatives. Organic chemistry is the study of structure, properties, composition, reactions, and preparation of carbon-containing compounds generally obtained from living organisms, which include hydrocarbons except oxides (CO, CO2,), metal carbonates, bicarbonates, cyanides, thoicyantes, cyanates and carbides.
This type of chemistry is important to the petrochemical, pharmaceutical, and textile industries. The gasoline, plastics, detergents, dyes, food additives, natural gas, and medicines are studied in the organic chemistry. All living organisms contain at least some amount of carbon in their body.
CH4
(methane, HC) ====== CH3Cl (chloromethane; Derivative of methane)
C2H6
(Ethane)
C2H4
(Ethene)
C2H2
(Ethyne)
C6H6 (Benzene)
Glucose (C6H12O6)
Sugar (C12H22O11)
Ethyl alcohol (C2H5OH)
Acetic acid (CH3COOH)
Chloroform (CHCl3)
With the exceptions of CO, CO2, metal carbonates, bicarbonates, cyanides, thiocyanates, cyanates and carbides, organic chemistry is the study of essentially all carbon compounds generally obtained from living organisms. In fact, it is the chemistry of hydrocarbons (carbon-hydrogen compounds) and their derivatives. [Most of the consumer products are organic in nature].
Some people also consider biochemistry as physiological chemistry and biological chemistry. The scientists that study biochemistry are called biochemists. It is concerned with the properties of biological molecules, including proteins, lipids, carbohydrates, and nucleic acids and chemical regulation of metabolism, the chemistry of vitamins, and biological oxidation.
Biochemistry helps us to understand how living things obtain energy from food. It tells that how disorder or deficiency of these biomolecules causes diseases. This branch is useful in medicine, agriculture and food science
It deals with the changes occurring in the nuclei of atoms accompanied by emission of radiation. It also deals with the characteristics of radioactivity or radioactive processes both natural and artificial, nuclear processes and atomic energy generated there. Radioactive elements are widely used in medicine as diagnostic tools and as a means of treatment, especially for cancer, preservation of food and generation of electric power through nuclear power reactors.
Analytical Chemistry
Analytical chemistry is concerned with the
qualitative and quantitative analysis of different substances. Analytical
chemistry is the analysis of material samples to
gain an understanding of their chemical
composition
and structure.
Analytical
chemistry is the branch of chemistry which deals with separation and analysis
of kind, quality and quantity of various components in given substance. It
deals with the methods and
techniques used
to determine the kind and quantity of various components in
a given substance.
Analytical chemistry seeks to determine the exact chemical compositions of substances.
It
used in chromatography, electrophoresis and spectroscopy.
In qualitative analysis
all the atoms and molecules present are identified, with particular attention
to trace elements. In quantitative analysis the exact weight of each
constituent is obtained as well. Stoichiometry is the branch of chemistry
concerned with the weights of the chemicals participating in chemical reactions.
Chemistry equations provide a powerful symbolic notation to express qualitative and quantitative details of chemical transformations i.e. chemical change. The calculation which deals with Stoichiometry (means 'to measure an element'), the fundamental concept is that the chemical equation, if interpreted correctly, is basis for all such calculations.
Analytical chemistry can be split into two main types, qualitative and quantitative:
(i) Qualitative inorganic analysis seeks to establish the presence of a given element or inorganic compound in a sample.
(ii) Qualitative
organic analysis seeks to establish the presence of a given functional group or organic compound in a sample.
Quantitative analysis seeks to establish the amount of a given
element or compound in a sample.
Most modern analytical chemistry is
quantitative. Quantitative analysis can be further split into different areas
of study. The material can be analyzed for the amount of an element or for the
amount of an element in a specific chemical species. The latter is of
particular interest in biological systems; the molecules of life contain
carbon, hydrogen, oxygen, nitrogen, and others, in many complex structures.
Techniques
There are a bewildering array of techniques
available to separate, detect and measure chemical compounds.
Separation of chemicals in order to measure the weight or volume of a final product. This is an older process and can be quite painstaking, but is an essential first step when dealing with certain mixtures of substances, like extracts from organisms.
Analysis of substances with devices using spectroscopy. Measuring the
absorption of light by a solution or gas, we can calculate the amounts of
several species, often without separation. Newer methods include atomic absorption spectroscopy (AAS), nuclear magnetic resonance (NMR) and neutron activation analysis (NAA).
Many techniques combine two or more analytical
methods (sometimes called "hyphenated" methods). Examples of this
include ICP-MS(Inductively-Coupled
Plasma - Mass Spectrometry), where volatilisation of a sample occurs in
the first step, and measuring of the concentration occurs in the second. The
first step may also involve a separation technique, such as chromatography, and the second a
detection / measuring device.
Techniques that involve volatilisation aim to produce free atoms of the elements making up the sample, which can then be measured in concentration by the degree to which they absorb or emit at a characteristic spectral frequency. These methods have the disadvantage of completely destroying the sample, and any species contained within it. These techniques include atomic absorption spectroscopy and ICP-MS / ICP-AES. These techniques can still be used to study speciation, however by the incorporation of a separation stage before volatilisation.
Environmental Chemistry
Medicinal Chemistry
It deals with synthetic organic chemistry, pharmacology and
various biological specialties. The medicinal chemistry is used in synthesis of
chemicals, bioactive molecules (Drugs) and pharmaceutical agents.
It deals with the process of polymerization and the products obtained through the process of
polymerization called polymers (such as plastics, synthetic fibers, papers etc.)
(CH2=CH2) ¾® (– CH2
– CH2 – )n
Green Chemistry/ sustainable
chemistry
It deals with study of processes and designing products, which are
composed of less hazardous substances.
Safer
chemical (polyphenylsulfon), less hazardous chemical (poly carbons) and
safer solvents are examples of green chemistry. The main purpose of this branch
is to use waste materials efficiently and improvement of energy efficiency in
chemical industry.
polyphenylsulfon (polymer made of aromatic rings linked by sulfone (SO2) groups) automotive, aerospace, and plumbing applications
It is concerned with design of chemical products and processes that minimize or eliminate the use or generation of substances hazardous to humans, animals, plants, and the environment.
The aim of green chemistry is to reduce chemical-related impact on human health and virtually eliminate contamination of the environment through dedicated, sustainable prevention programs. Green chemistry searches for alternative, environmentally friendly reaction media and at the same time strives to increase reaction rates and lower reaction temperatures.
The Principles & Examples
Green Chemistry
1. Prevention of waste wherever possible.
2. Promote “atom economy” (that is,
maximize the efficiency of production so that fewer by-products are made during the manufacture of
the final product).
3. Less Hazardous chemical
by-products Syntheses. ...
4. Designing safer, less-toxic chemical
products. ...
5. Use safer solvents and auxiliaries in chemical
processes. ...
6. Design energy-efficient
chemical-manufacturing processes. ...
7. Use of Renewable Feed stocks. ...
8. Reduce or avoid the production of
derivatives.
9. Use catalysts (most of which
require fewer materials to carry out a chemical
reaction).
10. Design for Degradation (Design chemicals
that break down into harmless products after they are used. Example: Biodegradable
Surfactants
11. Real-time Analysis for Pollution
Prevention Promote the development of real-time analysis of chemical products
before hazardous substances can form.
12. Inherently Safer Chemistry for Accident Prevention
Quantum Chemistry
It deals with application, mechanics and experiments of physical models in chemical system. It is also called molecular quantum mechanics.
Quantum chemistry is a branch of chemistry whose primary focus is the application of quantum mechanics in physical models and experiments of chemical systems. It is also called molecular quantum mechanics.
quantum mechanics, science dealing with the
behaviour of matter and light on the atomic and subatomic scale. It
attempts to describe and account for the properties of molecules and atoms and
their constituents—electrons, protons, neutrons,
and other
Quantum mechanics is the branch of physics that
deals with the behavior of matter and light on a subatomic and atomic level. It
attempts to explain the properties of atoms and molecules and their fundamental
particles like protons, neutrons, electrons, gluons, and quarks. The properties
of particles include their interactions with each other and with electromagnetic
radiation.
Quantum mechanics is the branch of physics that
deals with the behavior of matter and light on a subatomic and atomic level. It
attempts to explain the properties of atoms and molecules and their fundamental
particles like protons, neutrons, electrons, gluons, and quarks. The properties
of particles include their interactions with each other and with electromagnetic
radiation.
Here is a list of a number of things which
depend upon Quantum Physics for their operation.
1. Toaster
2. Fluorescent
light
3. Computer
& Mobile Phone
4. Biological
Compass
5. Transistor
6. Laser
7. Microscopy
8. Global
Positioning System (GPS)
9. Magnetic
Resonance Imaging
10. Telecommunication
1. Toaster
The bread toast which you enjoy while sipping
on your morning tea is able to make its way to your plate only because of
Quantum Physics. The heating element of the toaster glows red to toast a slice
of bread. Toasters are generally referred to as the reason why Quantum Physics
came into existence. The rod in the toaster gets hot, which, in turn, is
responsible for toasting the bread.
2. Fluorescent light
The light which you are getting from the tubes
or those curly bulbs is a result of a quantum phenomenon only. In fluorescent
lighting, a small amount of mercury vapour is excited into the plasma.
Mercury has the ability to emit light in the visible range. So, the next time
you switch on the lights of your room at night, make sure you thank Quantum
Physics.
3. Computer & Mobile Phone
The whole computer world is based on the
principle of Quantum Physics. Quantum Physics talks about the wave
nature of electrons, and, so, this forms the basis of the band structure
of solid objects on which semiconductor-based electronics are built. Not to
forget that we are able to manipulate the electrical properties of silicon only
because we can study the wave nature of electrons. Once the band structure is
changed, the conductivity alters as well. How can the band structure be
changed? Of course, Quantum Physics knows the answer!
4. Biological Compass
If you think that only the humankind has been
lucky enough to make use of Quantum Physics, you are totally wrong! According
to theories by scientists, birds like European Robin make use of Quantum
Physics to migrate. A light-sensitive protein called cryptochrome contains
electrons. Photons, after entering the eyes of the bird, hit cryptochrome, and
radicals are released. These radicals enable the bird to “see” a magnetic map.
Another theory suggests that the beaks of the birds contain magnetic minerals.
Crustaceans, lizards, insects, and even some mammals make use of such type of
magnetic compass. You might be surprised to know the type of cryptochrome which
is used for navigation by flies has also been found in the human eye! However,
its use is unclear.
5. Transistor
Transistors have widespread uses and are used
to amplify or switch electrical signals and electrical power. Looking
closely at the structure of transistors, we would realize that a transistor
consists of layers of silicon associated with other elements. Computer chips
are made by millions of these, and these computer chips form the
powerhouse of all the technological gadgets which have become central to human
existence. Had Quantum Physics not come into play, these chips would not have
been created and neither would desktops, tablets, laptops, smartphones, and
other gadgets have found their way into human life.
6. Laser:
The principle on which laser works is based on
Quantum Physics. The working of lasers involves spontaneous emission, thermal
emission, and fluorescence. An electron, when excited, will jump to a
high-energy level. However, it will not stay in the high-energy level for a
long time, and jump back to the lower energy state which is more stable; and,
thereby, emit light. The quantum mechanical state of the atom is also affected
by external photons which are at a frequency associated with the atomic
transition.
7. Microscopy
Electron microscopy has improved with
underlying principles of Quantum Physics. Quantum Physics in association and
electron microscopy have improved the imaging of biological samples. Moreover,
in differential interference contrast microscopy, a pattern of
interference is created by the beam of photons, which is then analyzed.
All-in-one, with Quantum Physics, microscopy has improved to a great extent,
and, therefore, a large amount of information from a sample can be obtained.
8. Global Positioning System (GPS)
Navigating to unknown locations has never been
easier as it has been with the aid of Quantum Physics. While using a mobile
phone for navigation, the GPS receiver in the phone is responsible for picking
up the signal from multiple clocks. The distance and time between your current
location and the destination are calculated by calculating different arrival
times from different satellites. Moreover, even the distance from your current
location from each satellite is also calculated. Each satellite is equipped
with an atomic clock, which relies on Quantum Physics only.
9. Magnetic Resonance Imaging
Magnetic Resonance Imaging, also known as
Nuclear Magnetic Resonance, involves the reversal of the spins of the electrons
in hydrogen nuclei. So, basically, we are talking of shift in energies; which
is nothing but one of the applications of Quantum Physics. The study of soft
tissues can easily be carried out with the use of MRI. Thanks to Quantum
Physics that the diagnosis and treatment of some life-threatening ailments have
been possible.
10. Telecommunication
Communication has been made extremely easy
because of the important role of Quantum Physics. Fibre optic telecommunication
has made possible two-way and quick communication. The fibre optic
telecommunication is possible only because of lasers, which are devices of
Quantum Physics.
Other Fields
Important Physical Chemists
1.2 Importance of Branches of Chemistry
Second; chemistry is an intellectual enterprise, a way of explaining our material world.
Third, chemistry figures prominently in other fields such as in biology, the advancement of medicines.
1.4 Importance of Chemistry in
daily Life (Role of Chemistry in Society)
The role of chemistry in daily life is unavoidable fact.
1. Cooking, eating and digestion of food are purely chemical processes.
2. Construction, cleaning and washing of our homes are dependable on chemistry.
3. The production of fertilizers, glass, plastic synthetic fiber, polymer, ceramics, petroleum products, soaps, and detergents are based on chemistry.
4. The diseases transmitted through impure drinking water as cholera, typhoid, dysentery, skin and eye infections can be controlled with the help of chlorine treatment to kill the pathogenic organism to obtain pure water.
5. The chlorine is most important chemical which used commercially to produce more than one thousands compounds which are used in chemical industry as bleaching agent, disinfectants, solvents, pesticides, refrigerates, PVC and drugs are miracles of chemistry.
1.5 Historical Back Ground of
Chemistry (Time Chronology of
Chemistry)
Enameling(ملمع سازی)
Enameling is the process of applying a thin coat of
finely ground glass to a metal, glass,
ceramics,
stone, or any material that will withstand the fusing temperature.
Major
achievements of Jabir Ibne-Haiyan
1.
|
Robert Boyle
|
(1627-1691 A.D)
|
Was regarded as the father of modern
chemistry.
|
2.
|
J. Black
|
(1728-1799 A.D)
|
Made a study of carbon dioxide.
|
3.
|
J. Priestly
|
(1733-1804 A.D)
|
Discovered oxygen, hydrogen chloride and
sulphur dioxide.
|
4.
|
Scheele
|
(1742-1786 A.D)
|
Discovered chlorine.
|
5.
|
Cavendish
|
(1731-1810 A.D)
|
Discovered hydrogen.
|
6.
|
Lavoisier
|
(1743-1794 A.D)
|
Discovered that oxygen constituted about
1/5th of air.
|
7.
|
John Dalton
|
(1766-1844 A.D)
|
Put forward atomic theory of matter &
concept of atomic weight.
|
8.
|
Gay-Lussac
|
(1778-1850 A.D)
|
Found out relative
atomic & molecular masses of many substances.
|
9
|
Avogadro
|
(1776-1856 A.D)
|
Found out relative
atomic & molecular masses of many substances.
|
10.
|
J.J. Berzelius
|
(1779-1848 A.D)
|
Introduced the idea of symbols, formulae &
chemical equations.
|
11.
|
Mendeleev
|
(1824-1907 A.D)
|
Published the periodic table of the
elements.
|
12.
|
Arrehenius
|
(1859-1927 A.D)
|
Put forward his ionic theory of ionization.
|
13.
|
M. Faraday
|
(1791-1867 A.D)
|
Discovered the laws of electrolysis.
|
14.
|
J.J. Thomson
|
(1856-1940 A.D)
|
Discovered electrons
|
15.
|
Henry Becquerel
|
(1852- 1908 A.D)
|
Discovered Radioactivity
|
16.
|
Madam Currie
|
(1867-1934 A.D)
|
Established radioactivity.
|
17.
|
Ken Rutherford
|
(1871-1937 A.D)
|
Discovered nucleus and put forward atomic
model.
|
18.
|
Neil Bohr
|
(1885-1962 A.D)
|
Improved
|
19.
|
Henry Moseley
|
(1887-1915 A.D)
|
Discovered atomic number that led to the development of
modern periodic table.
|
20.
|
Dr. Abdus Salam
|
(1926 -1996 A.D)
|
Put forward theory of unification.
|
1. Which branch of chemistry deals with the preparation of paints and papers?
(A) Biochemistry
2. In which branch of chemistry the metabolic processes of carbohydrate and proteins are studied?
(A) Biochemistry
3. Which branch of chemistry is concerned with atomic energy and its used in daily life?
(A) Biochemistry
4. Which branch of chemistry focuses on the structure and properties of naturally occurring molecules?
(A) Organic chemistry
5. PVC pipe is an example of which of the following?
(A) Biomolecule
6. Which of the following branches of chemistry involves the study of effects of harmful gases on the atmosphere?
(A) Polymeric chemistry
7. Metallurgical operations come under the category of ______.
(A) Physical chemistry
8. Proteins are studied under which of the following branches of chemistry?
(A) Physical chemistry
9. The composition of matter with the help of various methods and instruments is studied in
(A) Analytical chemistry
10. The ionic theory was presented by
(A) J.J. Berzelius
11. J. Priestly discovered
(A) Hydrogen
12. Who is regarded as the father of modern chemistry?
(A) Robert Boyle
13. Which scientist put forward theory of unification?
(A) Henry Moseley
14. The study of all elements and their compounds obtained from non-living sources is called
(A) Inorganic Chemistry
15. Chemistry is the study of
(A) Life
16. The Muslim period ranges from
(A) 1600 to today
17. He is known as the father of Al-chemy
(A) Robert Boyle
18. He first used opium as anaesthesia
(A) Jabir Bin Haiyan
19. Who first introduced the concept of symbols, formulae and chemical equation?
(A) Robert Boyle
20. Oxygen was discovered by
(a) J. Priestly
(b) J. Black
(c) Cavendish
(d) Scheele
(a) Oxygen
(b)Nitrogen
(c)Hydrogen
(d) Helium
22. Which of the following scientists suggested the symbols of the elements?
(a) James Chadwick
(b) J.J. Berzelius
(c) J.J. Thomson
(d) John Dalton
23. It is a trial idea
(a) Experiment
(b) Hypothesis
(c) Theory
(d) Scientific law
24. In scientific approach, it is considered only a trial idea
(a) Observation
(b) Hypothesis
(c) Theory
(d) Scientific law
25. It is the study of hydrocarbons and their derivatives
(a)Environmental chemistry
(b)Inorganic chemistry
(c)Organic chemistry
(d)Physical chemistry
26. He discovered hydrogen
(a) J. Black
(b) J. Priestly
(c) Scheele
(d) Cavendish
27. The father of modern chemistry is
(a)Robert Boyle
(b) Al-Razi
(c) Faraday
(d) J. Priestly
28. The branch of chemistry which deals with the emission of radiations from nuclei is called
(a) Physical chemistry
(b) Inorganic chemistry
(c) Nuclear chemistry
(d)Organic chemistry
29. Air contains about 21% of this gas by volume
(a) H2
(b) Cl2
(c) N2
(d) O2
30. The air we breathe in usually contains a higher proportion of:
(a) Nitrogen
(b) Oxygen
(c) Carbon dioxide
(d)Water vapours
31. Which of the following gases is used for respiration?
(a) Oxygen
(b) Nitrogen
(c) Carbon dioxide
(d) Helium
32. Natural gas mainly consists of
(a) Methane
(b) Ethane
(c) Propane
(d) Butane
33. The nucleus of an atom consists of
(a) Electrons and protons
(b)
Electrons & neutrons
(c) Protons & neutrons
(d) Protons only
34. Which one of the following is a liquid metal? (2009)
(a) Gold
(b) Silver
(c) Mercury
(d) Bromine
35. The medal given to the third position holder in any event is made up of: (2009)
(a) Gold
(b)Silver
(c)Bronze
(d) Brass
36. In the periodic table, the elements have been arranged in the order of increasing:
(a) Atomic number
(b)Mass number
(c)Chemical reactivity
(d) Density
37. Which one of the following is a compound?
(a) Air
(b) Coal
(c) Table salt
(d) Soda water
38.Which one of the following is a compound?
(a) Air
(b) Carbon
(c) Oxygen
(d) Steam
39. Atomic number of fluorine is
(a)7
(b)9
(c)11
(d)20
40. The molecular formula of sand is
(a)SiO2
(b)SiO3
(c)SiO4
(d)CaSiO3
41. Natural gas mainly consists of
(a)Ethane
(b)Methane
(c)Propane
(d)Butane
42. The formula of iron rust is
(a)Fe2O3
(b)Fe2O3.H2O
(c)Fe3O4
(d)FeO
43. The chemical formula of oleum (pyrosulphuric acid) is
(a) H2S
(b) H2SO3
(c) H2SO4
(d) H2S2O7
44. The most abundant and useful halogen is
(a) Fluorine
(b) Chlorine
(c) Bromine
(d) Iodine
45. It is the second most abundant element in the earth’s crust
(a) Sulphur
(b) Iron
(c) Nitrogen
(d) Silicon
46. The chemical formula of sulphuric acid is:
(a) HCl
(b)HNO3
(c) HSO4
(d) H2SO4
47. Who discovered oxygen?
(a)J. Black
(b)J. Priestly
(c)Scheele
(d)Cavendish
That was really nice + easy to understand 🙂
ReplyDeleteThanks sir it is easy to understand from here😇
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