Class 11 Chemistry
Chapter 1 - Some Basic Concepts of Chemistry.
1. CHEMISTRY
Chemistry (derived from the Egyptian word kēme (chem), which means
"earth") is a science that studies the composition, structure and properties of
matter and the changes it undergoes during chemical reactions. Chemistry is
often referred to as core science because it plays a role in linking physical
sciences (including chemistry) with life sciences and applied sciences (such as
medicine and engineering).
Chemistry is divided into following branches:
1.1 Physical chemistry
The branch of chemistry which deals with macroscopic as well as physical
phenomena in a universe. It is generally the impact of physical property on the
chemical property as well as structure of a substance.
1.2 Inorganic chemistry
The branch of chemistry that studies compounds that do not contain carbon and
hydrogen atoms is called "inorganic chemistry." Simply put, it is the opposite
of organic chemistry. Substances that do not have carbon-hydrogen bonds
include metals, salts, and chemicals.
1.3 Organic chemistry
The discipline which deals with the study of the structure, composition and the
chemical properties of organic compounds is known as organic chemistry. It
involves the study of Carbon and its compounds.
1.4 Biochemistry
Biochemistry is that branch of chemistry that explores the chemical processes
in organisms and associated with them. It's a laboratory-based science that
connects biology and chemistry. By using chemical knowledge and technology,
biochemists can understand and solve biological problems
1.5 Analytical chemistry
It is the branch of chemistry which uses instruments and analytical techniques
to determine structure, functionality and properties of a substance.
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, 2. MATTER
Matter is defined as any thing that have some mass and also occupies a certain
volume in a space.
Generally matter is classified into three phases:
• Solid- The substance which have a definite shape as well as maintain
its volume as per it’s shape, also they have least freedom of movement.
e.g., sugar, iron, gold, wood etc.
• Liquid- A substance is a substance which generally possess the shape
of a container but have a fixed volume. Also liquids have the property
to flow or to be poured. E.g., water, milk, oil, mercury, alcohol etc.
• Gas- Substances which do not have a definite volume as well as
definite shape. Gases generally completely fill the container they are
kept in. E.g., hydrogen, oxygen etc.
The three states are interconvertible by changing the conditions of
temperature and pressure as follows:
(taken from original pdf)
3. CLASSIFICATION OF MATTER AT MACROSCOPIC LEVEL
Matter can further be classified into following at bulk or macroscopic level:
(a) Mixtures (b) Pure Substances.
These can be further classified as shown below:
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