This document provides a history of chemistry from ancient Greece to the 21st century. It discusses how chemistry originated from Aristotle's theory of four elements of earth, water, air and fire. Key developments included Georg Agricola's work on mining and metallurgy in the 16th century, Robert Boyle's experimental methods in the 17th century, Lavoisier's discoveries on combustion and being the "Father of Modern Chemistry" in the 18th century, Dalton's atomic theory and the law of conservation of energy in the 19th century, and discoveries of the atomic nucleus, neutron and superconductivity leading into the 21st century. The document traces the major advances in chemistry over the centuries.

1. CHEMISTRY
21st CENTURY
• NAME : Kushang N. Choksi
• Roll No : 24
• Sub : Textile Technology
•Clg:

2. What is Chemistry ?
• Chemistry is a branch of
physical science, and the
study of the substances of
which matter is composed.
• Chemistry is a branch
of physical science that
studies the composition,
structure, properties and
change of matter.

3. History of Chemistry :
• A basic chemical hypothesis
first emerged in Classical
Greece with the theory
of four elements as
propounded definitively
by Aristotle stating that
that fire, air, earth and
water were the fundamental
elements from which
everything is formed as a
combination

4. Uses of Chemistry :
• Everything is made of
chemicals. Many of the changes
we observe in the world around
we see that caused by chemical
reactions. Chemistry is very
important because it helps us to
know the composition,
structure& changes of matter.
All the matters are made up of
chemistry.

5. Starts in 16th century :
• In the 16th century, among
them Georg Agricola, who
published his great work De
re metallica in 1556. His
work describes the highly
developed and complex
processes of mining metal
ores, metal extraction and
metallurgy of the time.
• The work contains some of
the earliest modern ideas
of atoms, molecules,
and chemical reaction, and
marks the beginning of the
history of modern chemistry

6. Starts in 17th century :
• In the 17th century, a
synthesis of the ideas of these
two disciplines, that is
thedeductive and
the experimental, leads to the
development of a process of
thinking known as
the scientific method.
• The experimental methods of
modern science are
considerably advanced by the
work of Robert Boyle during
the 1660s

7. Starts in 18th century :
• Two natural processes and
rusting, particularly intrigue the
chemists of the 17th and 18th
centuries.
• During the 18th century
chemistry made great advances.
In 1751 a man named Axel
Cronstedt discovered nickel. In
1766 Henry Cavendish isolated
hydrogen and studied its
properties.

8. • Perhaps the greatest chemist of
the 18th century was Antoine
Lavoisier. He also discovered
the role of oxygen in
respiration and corrosion of
metals.
• Antoine Lavoisier was a French
nobleman and chemist central
to the 18th-century Chemical
Revolution and a large
influence on both the histories
of chemistry and biology. He is
widely considered to be the
"Father of Modern Chemistry”.

9. Starts in 19th century :
• During the 19th century science
made great progress.
• In 1803 John Dalton published
his atomic theory.
• In 1847 the German Hermann
von Helmholtz formulated the
law of the Conservation of
Energy, which states that
energy is never lost but just
changes from one form to
another.

10. • Meanwhile geology made
huge strides. Charles Lyell
saw that rocks were formed
by processes we see today. In
1830 he published his book
Principles of Geology.
• In 1837 a Swiss, Louis
Agassiz realized that a vast
sheet of ice had once covered
northern Europe..

11. Starts in 20th century :
• During the 20th century
science continued to go
forward at fantastic speed.
• During the 20th century
scientists came to understand
the atom.
• In 1910 Ernest Rutherford
discovered the atomic nucleus.
He realized that almost all the
mass of an atom is in the
nucleus with electrons orbiting
it. In 1932 James Chadwick
discovered the neutron.

13. • The most famous physicist of
the late 20th century is
Stephen Hawking (1942-).
Hawking is known for his
research into black holes,
relativity and cosmology.

14. Starts in 21st century :
• Two more innovations of the
late 20th century deserve at
least brief mention, especially
as they are special focuses of
the chemical industry in the
21st century.
• The phenomenon
of superconductivity was
discovered in 1911 at
temperatures very close
to absolute zero.