Some Basic Concepts of Chemistry Class 11 Part 1
Summary
TLDRThis chemistry class video focuses on the fundamental concepts of chemistry, explaining that it is the study of elements, molecules, and compounds, and their properties and structure. It highlights the importance of chemistry in everyday life, including its applications in medicine, food, and agriculture. The video also discusses the classification of matter into solids, liquids, gases, and further into mixtures and pure substances, including elements and compounds. It emphasizes the balance between the benefits and potential hazards of chemical usage.
Takeaways
- 🔬 Chemistry is the study of elements, their combinations to form molecules and compounds, and the properties, structure, and chemical nature of these molecules.
- 📚 The periodic table is a fundamental tool in chemistry, organizing the 120 known elements.
- 🌐 Chemistry is essential in everyday life as it is involved in the composition of all matter, including living and non-living things.
- 🔑 The concept of matter is central to chemistry, defining anything in the universe that occupies space and has mass.
- 🧬 Biology is intertwined with chemistry, as living organisms are composed of chemicals and undergo chemical reactions.
- 💊 Chemistry plays a crucial role in medicine, with chemicals like cisplatin, taxol, and azido thymidine used in treatments for diseases like cancer and AIDS.
- 🥫 Chemicals are prevalent in food, used as preservatives to extend shelf life and as food colors to enhance appearance.
- 🌱 Agriculture relies on chemicals such as pesticides, insecticides, and fertilizers to protect and nourish crops.
- 🏭 Chemicals are utilized across various industries, including textiles and paint, highlighting their widespread application.
- ♻️ While chemicals are beneficial, overuse of synthetic chemicals can have detrimental effects on the environment, such as ozone depletion and air pollution.
- 🔍 Matter can be classified into solids, liquids, and gases based on physical states, and further into mixtures (homogeneous and heterogeneous) and pure substances (elements and compounds).
Q & A
What is the definition of chemistry as mentioned in the script?
-Chemistry is defined as the study of the structure, composition, and properties of matter. It involves not only the study of elements arranged in the periodic table but also the study of molecules, their properties, structure, and chemical nature.
How many elements are there in the periodic table as per the script?
-There are 120 elements in the periodic table.
What is the role of chemistry in biology according to the script?
-Chemistry plays a crucial role in biology as living organisms' bodies contain chemicals, elements, and compounds, and numerous chemical reactions take place within these bodies.
Why is chemistry important in everyday life?
-Chemistry is important in everyday life because chemicals are present in everything we interact with, from the food we eat to the medicines we take. It is involved in various industries and plays a significant role in our daily activities.
What are the two medicines mentioned in the script that are used in cancer therapy?
-The two medicines mentioned for cancer therapy are cisplatin and taxol.
What is the chemical used for AIDS patients as per the script?
-Azido thymidine, also known as AZT, is the chemical used for AIDS patients.
How is matter classified based on physical state?
-Matter is classified into three categories based on physical state: solids, liquids, and gases.
What are the characteristics of a solid as described in the script?
-Solids have a definite shape and size, and the atoms or molecules are arranged in a closely packed fashion with strong attractions between them, resulting in a fixed shape and inability to move freely.
How does the script differentiate between a homogeneous and a heterogeneous mixture?
-A homogeneous mixture has a uniform composition throughout, like sugar water, whereas a heterogeneous mixture has a non-uniform composition, with components separated in space, such as sand in water where sand settles at the bottom.
What is the difference between an element and a compound as per the script?
-An element is a pure substance made up of the same type of particles, like an iron rod made up of iron atoms. A compound is a pure substance made up of different particles, like water, which is made up of hydrogen and oxygen.
Why should the use of artificially synthesized chemicals be limited according to the script?
-The use of artificially synthesized chemicals should be limited because they can be more dangerous to the environment and can destroy the well-being of mankind if overused.
Outlines
🔬 Introduction to Chemistry
This paragraph introduces the subject of chemistry, emphasizing its importance in everyday life. It explains that chemistry is not just the study of elements but also the study of how these elements combine to form molecules and compounds. The periodic table, which arranges these elements, is mentioned as a foundational concept. The paragraph further discusses that chemistry is the study of the structure, composition, and properties of matter, which includes both living and non-living things. It concludes by highlighting the interdisciplinary nature of chemistry, its relevance to other sciences like physics and biology, and its applicability in various fields.
💊 Chemistry's Role in Medicine and Daily Life
This section delves into the practical applications of chemistry, particularly in the field of medicine. It mentions how chemicals are used to cure diseases, with specific examples including cisplatin, taxol for cancer therapy, and azido thymidine for AIDS patients. The paragraph also touches on the use of chemicals in the food industry, such as preservatives and food colors, and in agriculture through pesticides and fertilizers. However, it warns of the potential negative impacts of chemicals, like the depletion of the ozone layer by chlorofluorocarbons and air pollution from factory emissions, underscoring the need for responsible chemical usage.
🧪 Classification of Matter
The script explains the classification of matter based on its physical state into solids, liquids, and gases. Solids are characterized by a definite shape and size due to closely packed atoms or molecules with strong intermolecular attractions. Liquids lack a definite shape but have a volume, with particles that can move more freely due to weaker attractions. Gases have neither a definite shape nor size, and their particles are far apart with minimal attraction, allowing for random movement. This classification is fundamental to understanding the nature of matter in chemistry.
🌐 Mixtures and Pure Substances
This part of the script discusses the classification of matter into mixtures and pure substances. Mixtures are combinations of two or more substances that can be mixed in any ratio, such as sugar in water. Pure substances, on the other hand, consist of a fixed ratio of elements, like water (H2O). The paragraph further differentiates mixtures into homogeneous (uniform composition throughout, like saltwater) and heterogeneous (non-uniform composition, like sand in water) mixtures. Pure substances are classified into elements, which are made up of the same type of particles, and compounds, which consist of different particles combined in a fixed ratio.
📚 Recap and Preview of Upcoming Topics
The final paragraph summarizes the classification of matter based on physical state and general composition. It recaps the distinctions between solids, liquids, gases, mixtures (homogeneous and heterogeneous), elements, and compounds. The speaker then teases the next video, which will focus on the properties of matter, encouraging viewers to subscribe for more easy-to-understand lessons on chemistry.
Mindmap
Keywords
💡Chemistry
💡Elements
💡Molecules
💡Compounds
💡Matter
💡Physical State
💡Solids
💡Liquids
💡Gases
💡Mixture
💡Pure Substance
💡Element
💡Compound
Highlights
Introduction to the basics of chemistry and its importance in everyday life.
Chemistry defined as the study of elements, molecules, and their properties.
Explanation of how elements combine to form molecules and compounds.
Chemistry's role in studying the infinite variety of molecules in nature.
Matter defined as anything in the universe that occupies space and has mass.
Chemistry redefined as the study of the structure, composition, and properties of matter.
Interconnection of chemistry with other branches of science like physics and biology.
Importance of chemistry in medicine, particularly in cancer therapy and AIDS treatment.
Chemicals' widespread use in food, agriculture, and various industries.
The potential dangers of chemical use, such as ozone layer depletion and air pollution.
The need for responsible use of chemicals to avoid environmental harm.
Classification of matter into solids, liquids, and gases based on physical state.
Characteristics of solids, including definite shape and closely packed atoms.
Explanation of liquids' lack of definite shape but presence of volume.
Gases defined as having no definite shape or size and free movement of particles.
Matter can also be classified as mixtures or pure substances.
Mixtures are combinations of two or more substances without a fixed ratio.
Pure substances have a fixed ratio of elements, like water (H2O).
Mixtures can be homogeneous, where composition is uniform, or heterogeneous.
Pure substances are further divided into elements and compounds.
Elements are pure substances made of the same type of particles, like an iron rod.
Compounds are pure substances made of different particles, like water (H2O).
Transcripts
[Music]
hey everyone
welcome to homeschool and welcome to
class 11 series
chemistry uh see we have already done a
video on
class 11 chapters overview where i
explained about what are the chapters
that is there in class 11 chemistry
and a brief introduction about them
isn't it and
this is the video on the very first
chapter that is basic concepts
of chemistry so here first of all let us
deal with what is actually the chemistry
is and what is the importance of
chemistry in everyday life
clear so if i ask you to define the
chemistry
how do you define a chemistry see many
of them who tell chemistry
is the study of elements right and we
have so-called
elements in our nature right now 120
elements and they are beautifully
arranged
in the form of a table called periodic
table
we all know the basics of periodic table
that we have learnt in class 10
isn't it see according to that people
who think that
it is the study of those elements not
only the study of
those elements and you know these
elements what do they do
the elements would combine with each
other to
form molecules and compounds isn't it
say for example you have one oxygen atom
would combine with
another oxygen atom you would get oxygen
molecule
or you have hydrogen molecule itself
that would combine with oxygen molecule
and you may get
a new compound called h2o right
see these are the elements they are
combining to give molecules
so chemistry is not only the study of
these elements that is very nicely
arranged in a periodic table
it is also the study of these molecules
it is the study that involves how these
atoms or elements have combined
to give molecules and it is the study of
those molecules their properties their
structure
their chemical nature and everything
right
say chemistry is the study of infinite
molecules
and you don't have limited number of
molecules in our nature you have
infinite endless countless number of
molecules
so it is the study of all those
molecules
nature structure composition and what
not
it is everything right and where are
these
molecules or compounds or elements
present
they are present in the matter itself
right so what do you mean by
matter this is not a new word for you
say matter is anything in the universe
uh that occupies space isn't it
occupies space and has
some mass such a thing is called
matter are we matter definitely we are
matters
and this chalk piece is a matter air is
a matter
everything is a matter because if you
take this chalk piece it has certain
mass
and it is occupying some space in this
universe
so i can call this chalk piece as a
matter like that if you see
all living things that you see from your
eye and non-living things that you see
from your
eye everything is a matter right
so i will redefine chemistry now here
i can define chemistry as it is the
study of
study of structure composition
and properties
of matter here so this becomes a perfect
definition for chemistry it's not only
the study of
elements it is the study of that
infinite countless number of molecules
and where are these countless number of
molecules and these elements present
definitely in so-called matter so they
are present in
everything that we see from your from
our eyes isn't it
so ultimately i can say study of
structure
composition and properties of matter
is called chemistry isn't it
say and now can you able to tell me
what is the importance of chemistry why
do we need to study
this branch of science and this
branch of science is dependent on
other branches of size you know all the
branches of signs are
interconnected with each other what are
the different branches of science
physics is a branch biology is a branch
chemistry is a branch
right so these are all various branches
of science and they are all
interdependent one branch is dependent
on another
right and you know what what do you mean
by biology
biology is a study of life biology is a
study of human body
organisms body plants body and what does
the body contain
any living organisms body contain
the chemicals the so it's a matter right
so it contains lots of elements lots of
compounds and too many chemical
reactions
are taking place inside the body right
say here also chemistry is
involved so there is no biology without
any chemistry
and there is no chemistry without any
biology right
so similarly even our physics is
dependent on chemistry chemistry is
dependent on physics so
all these branches are interconnected
interdependent with each other
okay so now what is the importance of
studying chemistry in everyday life
phase
we see chemicals everywhere right we eat
chemicals the food we eat
is a chemical only right and the water
we drink is a chemical only like that if
we see
morning soon after we get up until we go
to the bed
we are connected with so-called
chemicals
all around they may be natural they may
be artificial chemicals right
but definitely we depend on chemicals
right and let us see some examples
chemicals
are widely used in the field of
medicine right see nowadays
every disease can be cured with the help
of
medicine and this medicine is nothing
but chemicals
they these chemicals are prepared by
various other
reactions i can say and you know two
such chemicals i will
mention here they are very very
important there is a chemical called
cis plating these are the things
mentioned in your ncip books
so i'm mentioning here cis platinum and
another uh medicine called taxol
so these are the two medicines which are
used
in cancer therapy so
to cure a cancer we use certain
chemicals they give treatment with the
help of chemicals called chemotherapy
so in chemotherapy cisplatin and taxol
are the chemicals which are
used right and also
there is another chemical called
acetothymidine
azido thymidine and this is the chemical
which is used uh for aids patients
used for aids patients say
uh likewise if we go on mentioning the
chemicals you know the parasite
we take when we get a fever analogistics
that we take as pain killers you know
all these are various chemicals only
right
so chemicals play a lot of importance in
the field of
medicine and now i can say chemicals in
food
chemicals in food even in the food
industry
the preservatives that we use
preservatives that means uh
using this we can store food for a
longer time
uh they are called as preservatives and
we can use food colors
right so various other things we use in
the food industry also
and the chemicals in agriculture say
agriculture uh nowadays
too many different types of farmings are
available
natural or artificial chemical usage
farming
whatever it is the chemicals are widely
used
so chemicals are used in the form of
pesticides right insecticides
and what not you can use them as
fertilizers
right so in a different way it can be
used even in the agriculture
right like that if we go on mentioning
there are various industries textile
industry paint industry
uh you know every industry uh chemicals
are used
and now we have lots of uses with
different types of chemicals at the same
time
we have so many side effects of using
chemicals also
say for example chlorofluorocarbons that
we use in the refrigerators
cause you know ozone layer depletion
isn't it and likewise the gases like
sulphur dioxide nitrogen dioxide
uh these are the gases that come out
from the factories
even they cause the air pollution you
know they are responsible for
acid rain likewise if we go on telling
the dangerous aspects of chemicals
numerous numerous things are there say
one point i would like to tell you is
yes we use chemicals for the benefit of
man at the same time
we have to limit the usage of
artificially synthesized chemicals
because they are more dangerous to the
environment
so we have to use them in a
limited way otherwise it would destroy
uh the well-being of mankind right so
chemicals has
both benefits as well as uh hazardous
things also
so this point we have to keep it in a
mind and then
a proper usage of chemicals may give
enough benefit to a man but when you
overuse it
it could destroy the well-being of man
isn't it so this is some introduction
about
uh the chemistry and the importance of
chemicals and dangerous aspects of
chemicals
and now without wasting much time let me
move on to the next
concept that is nature of matter
because chemistry is all about
the study of matter isn't it so let us
see what are the different
types of matter i mean matter can
again be classified into so many types
and let us see what are those types and
what is their
nature see guys based on the physical
state
matter can be classified into three
categories
one is solids liquids
and gases isn't it this way of
classification we have
learned it in our earlier classes also
so this classification
is mainly based on
physical state of matter physical
state clear okay so now what do you mean
by solid say this chalk piece is a solid
board is a solid
say solids are a type of a matter
which have definite shape and size
so they have definite shape and
size isn't it and you know uh
in a solid the atoms are arranged
in a closely packed fashion i mean
between
one atom and another atom or these guys
may be
molecules see matter is made up of
atoms or molecules so it may be
an atom or it may be a molecule of
matter
between the molecules or atoms
you have lots of attraction between them
okay so that is the property of solids
clear
that is the reason they have a proper
shape
and a proper size okay
and coming to the liquids and liquids
do not have a definite shape
no definite shape
but they have volume
they have so called volume okay
and in a liquid uh whatever the atoms
are molecules
present in the liquid matter they can
move
they have a ability of moving it's
because
you know the atoms or a molecules
would have a space between them that's
the reason
there is no much attractions between the
atoms and
molecules of liquids that's the reason
they can
freely move whereas in the solid there
is no movement of atoms and molecules
okay fine and what do you mean by a
gases
say oxygen gas hydrogen gas which are
present in the atmosphere
uh what do they have they do not have
any
shape and no shape no
size also clear and
you know if you see the atoms or
molecules in a gas
you can see lots of spaces are there in
between
and there are no much attractions
between the atoms or molecules
so they can very nicely move in a
random way isn't it and you can see the
atoms and molecules of solid how i have
shown you it
is there's no gap between them and they
are closely packed
uh that's the reason they have a
particular shape and they can't move
and here these guys have little
attractions
and uh you know they have little spaces
between
each other and they are free to move and
here
uh the freedom of movement is too much
they can move very nicely in a random
way
say this is some basic aspects about
solids liquids and gases clear fine
and now the matter can also be
classified
uh into you know mixture and
pure substance clear there is another
classification of
matter that we have already studied in
our previous classes
it been can be classified
as mixture and pure substance
and now let us discuss what do you mean
by
a mixture and mixture is nothing but
a combination of combination
of two or more
substances substances is nothing but any
kind of a matter
if two or three types of matter is
mixed together then we call it as
mixture
okay and you know they have been
combined
in any ratio in any ratio
okay they they there is no fixed ratio
for the mixture say for example if i say
sugar
in water sugar in
water when i put a spoon of sugar in
water it becomes a mixture
sugar is one type of matter water is
another type of matter
this is one substance this is another
substance and
i'm combining both of them so i can call
this as a mixture now
okay and you can mix these things in any
ratio
right so you can add one spoon of sugar
in one liter of water or you can
add once one spoon of water
in so much amount of sugar you know
there's no perfect ratio like this much
amount of sugar has to be combined in
this much amount of water
right so you can mix these things in any
proportion in
any ratio then you will normally call it
as
mixture okay and now what do you mean by
a pure substance
you know pure substance is a pure
chemical substance
where two substances i mean two
different
patterns can be combined but with a
fixed ratio
so here you have a fixed ratio
okay say for example water water
is called as a pure substance okay you
you can ask me like it's a combination
of hydrogen
and oxygen no ma'am how you will call it
as a pure substance
i have to call this as a mixture no you
know this is a doubt you will get
but you see how is water formed water
has
formed by the combination of two atoms
of
oxygen with one atom of oxygen isn't it
so only then water is formed when two
hydrogen atoms would combine with one
oxygen atom
only then water is formed that means
they are combining in a fixed ratio they
are not combining
in how many how much ever they want
however
they want isn't it say when the two
different
matters they this is one element this is
an
another element both are matters only
but combining in a fixed ratio
so water is called as a pure substance
and sodium metal is called as a pure
substance oxygen
gas is a pure substance right a single
element or
it may be a molecule or compound but if
it is combined in a fixed
ratio then we can call it as a pure
substance
clear fine and now coming to the mixture
mixture is again classified into two
types
one is homogeneous mixture
and other one is heterogeneous mixture
right okay so what do you mean by
homogeneous mixture
here the composition is uniform
throughout
composition is uniform
what do you mean by composition is
uniform here
say okay let me give one example first
sugar water sugar water or
salt water is the example and let me
give an example here heterogeneous
heterogeneous in the sense
composition composition
is not uniform
observe the example sand
sand plus water imagine if you
put a one spoon of sand in a beaker of
water
will you have sand particles throughout
the water
no right all the sand would go at the
bottom and they would settle
i mean sand is there only at the bottom
of the water
what about the top surface of water it
is pure it's only a water
there will not be any sand that means in
entire water
the sand particles are not present right
they they are restricted to one
particular
area in water medium isn't it so that's
what we mean by heterogeneous
that's what we mean by composition is
not uniform
that means sand particles are not
present
all through the water right they are
restricted to one particular place they
went
to the bottom and they got settled isn't
it but
if you put one spoon of sugar in water
and nicely when you mix it
what happens you will have sugar
particles throughout the water
at the bottom of the water you have
sugar plus water
on the surface of the water also you
have sugar particles
in the middle of the beaker also you
have sugar particles isn't it
so sugar particles are spread evenly
uniformly throughout the water right
that such a mixture we will call it as
homogeneous
here everyone that's all and now pure
substance is again classified
into element and
compound okay now
what do you mean by element element
are those substances which are
made up of with same particles
they are made up of with same particles
so what do you mean by the element is
the pure substance made up of same
particles
if you take up iron rod okay say
at every corner of this particular iron
rod
you have the same particles called iron
atoms
so this iron rod would have cross of
iron atoms but
all are iodine atoms only you don't find
any other atom in between
right say such a substance
such a pure substance which is made up
of
same particles here the particle is atom
isn't it so matter is made up of atoms
and molecules
matter is made up of molecules molecules
is again
formed by the combination of atoms so
ultimately
what is the smallest particle of matter
atoms
so if a pure substance is made up of
same type of particles
then we call it as element so what do
you mean by compound
compound means made up of different
particles
compound is a pure substance made up of
different particles say for example
water here
okay so water is pure one but it is made
up of
two different elements that is hydrogen
and oxygen
isn't it so this is some basic
introduction about
how matter is classified based on the
physical state we can classify this
into solids liquids and gases and based
on the general way i can classify matter
into mixture impure substance
mixture is again into homogeneous
mixture and heterogeneous mixture
pure substance is again into element and
compound
so this is all about nature of
matter so in my next video we will
discuss about
the properties of mata okay meet up in
the next
session till then take care and do
subscribe our channel to learn the
concepts in the easiest way
thank you so much
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