Branches of Science: three

• Physics: Deals with

▪ different forms of energy like light, sound, heat, electrical etc.
▪ Occurrence of physical changes corelated with energy changes.
• Chemistry: Deals with
▪ Study of substances, their composition, and properties.
▪ Their interaction with other substances and the chemical changes that they
undergo.
• Biology: Deals with living orgasms like plants (Botany) and animals (Zoology)

Branches of Chemistry: Two

Inorganic chemistry: Study of innumerable elements and compounds – metal/ non-metal
Organic chemistry: Study of specific carbon compounds built up mainly of carbon and hydrogen.
Apparatus used in chemistry:
Basic Apparatus:
Name Photo Characteristics
• Open at one end and closed at other.
• Varies in size – 4 cm to 15 cm
Test • Test tubes are used for heating purposes.
tubes • Hard glass test tube made of pyrex is called boiling
tube. Boiling tube is resistant of chemicals and used for
special purposes.
• Glass container with varied size
Beaker
• Used for holding, pouring and mixing solutions
Round • Used for gas preparation – where heating is required.
bottom • Due to round bottom, the heat is uniformly distributed
flasks throughout for heating.

Flat
• Used for gas preparation – where heating is not
bottom
required.
flasks

Conical • For storage of various liquids and mixing different

flasks solutions

• For carrying out distillation experiments

Retort
• This includes acid distillations.
Holders:
Name Photo Characteristics
• Metallic clamp fixed on wooden handle.
Test
• Used for holding a test tube while heating.
tube
• The wooden handle is poor conductor of heat; hence
holder
handling is easy.
• It is a wooden or plastic stand with holes and upright
Test tube pegs.
stand • Test tubes are kept straight through the holes.
• Washed test tubes can be kept inverted on the pegs.

• Contains an iron rod with a rectangular heavy iron

base.
Retort • A clamp is mounted on the rod, which can be raised
stand or rotated.
• It is used for holding the apparatus – used during
chemical reaction.

• Made up of iron triangle on three iron legs.

Tripod • Supports the glass apparatus (flask or retort) placed
stand on it.
• Also supports wire gauze.
• A rectangular wire mash with asbestos at its center. It
is placed between tripod and glass apparatus.
Wire • It prevents the glass apparatus from cracking on
Gauze heating from below.
• It initiates even distribution of heat to the bottom of
the apparatus.
Apparatus used for gas collection:

Name Photo Characteristics

• It consists of burner tube, an air regulator (collar) and
a base.
Bunsen • Burner tube is a long tube, at the end of which, the
Burner gas burns.
• Air regulator is a metal cylinder with holes for
regulating the flames.
• Base is connected to the gas tap for inlet of gas.
• It is a long glass tube with a broad inlet at the top.
• It allows entry of reactants into the round bottom
flasks.
Thistle
• Its lower end dips into the solution in the flask,
funnel
otherwise gas formed may escape through thistle
funnel and not pass-through delivery tube and get
collected.
• It is a thin glass tube of various shapes.
Delivery
• It is used for connecting and transferring gas from one
tube
apparatus to another.

• Clay vessel provided with two outlets one on the side

and one at the top.
Beehive • It is used for collecting gas by the downward
shelf displacement of water.
• The beehive shelf is kept in a trough of water and the
gas jar inverted over it. The gas is collected in the jar.
 • It is a long glass jar closed at one end and open at
other.
Gas Jar • For collecting the gas by different methods.
(Mentioned below)

• Made of glass and available in various sizes.

• It used for pouring reactants from one vessel to
another or into the thistle funnel.
Funnel
• It is used for carrying out filtration using wetted filter
paper. The filter paper is made into conical shape and
placed inside the funnel.
Measuring apparatuses: used to measure fixed volumes.
Name Photo Characteristics

• It is used by sucking the liquid upto the marked level

Pipette and closing the open end.
• The measured liquid is then poured out by removing
the thumb.

• By pouring the liquid from the top of the burrette up

Burrette to the marked level.
• Removing dropwise by opening the tap below.

Measuring • By pouring the liquid at the marked level and pouring

cylinder it out.

Different types of gas collection methods:

• Downward displacement of water:
o The gas jar is filled with water and inverted on the beehive shelf so that the water is
displaced downwards, and gas is collected upwards.
o It is used for insoluble or slightly soluble gases like oxygen and nitrogen.
• Downward displacement of air:
o This method is used for gases which are soluble in water and lighter than air. For
example, ammonia
• Upward displacement of air:
o This method is used for gases which are soluble in water and heavier than air. For
example, hydrogen chloride.
Importance of Chemistry:

In Agriculture: Two ways:

• Fertilizers: To improve fertility and provide nutrients to the plant.
Examples:
▪ Ammonium Nitrate: Most common fertilizer
▪ Urea: An important source of Nitrogen.
▪ Phosphatic fertilizers: Super phosphate.
• 90% of fertilizers are in solid form.
• Aqueous solutions of ammonia and ammonium nitrate are examples of liquid
fertilizers.
• Pesticides: Chemicals added to the soil to kill pests.
o They protect plants from weeds, fungi and insects.
o Three types:
Herbicides: kill or inhibit the growth of unwanted plants.
Insecticides: Destroys insects which harms the plants
Termiticides
o Pesticides may come in contact with other living organisms and disrupt the balance
of the ecosystem.

Products: that uses chemistry

Food Refined oils, butter, Cheese
Construction Mortar, cement, glass
Clothing Natural fabrics like silk
Household Cooking gas, food preservatives, specific utensils, and electronic items.
Daily usages Paints, dyes, perfumes, paper, ink
Industrials Metal and alloys found in machines
Petroleum Petrol, Kerosene, and diesel oil

Development of chemistry:
Alchemists:
o the people who were the predessors to the modern chemists.
o They were discredited because they brought occult and religion to scientific
research.
o They transformed or created substances through magical process.
o Nicolas Flamel in 14th century transformed metals into gold.
Philosopher’s stone:
o It was a legendary substance which converted inexpensive metals like lead or
mercury into gold or silver in Europe.
 o It was also known as elixir of life and most sought after in western alchemy.
o From Middle Ages to 17th century, philosopher’s stone was on priority and it helped
alchemists in developing the process to extract metals and other pathbreaking
avenues in chemistry.
o Towards the end of 17th century, scientific processes involving modern chemistry
started.
o Today alchemy is considered as pseudoscience.
Fill in the blanks:
Science is bifurcated into branches.
Major branches of science are , and .
Physics deals with different forms of .
Chemistry deals with , and .
Two branches of Biology are and .
Two branches of Chemistry are and .
Organic chemistry is primarily study of are .
Inorganic chemistry includes study of and .
Carbon compounds are mainly built of and .
Hard glass test tube made of is called boiling tube.
Flasks are used for heating.
Flasks are used for mixing solutions.
are used for distillation experiments.
Stand is used for holding the flasks during chemical reactions.
Retort stand has , and
.
Tripod stand support and .
Wire gauze has at the center.
Bunsen burner consists of , and
.
Is used to regulate the flame in Bunsen burner.
Is a long glass tube with a broad inlet at the top.
Is used to collect the gas by downward displacing the water.
 Method is used to collect insoluble or slightly soluble gases.
are examples of insoluble or slightly
soluble gases.
Method is used to collect gases which are soluble in water and lighter
than air.
Is an example of gas which is soluble in water and lighter than air.
Method is used to collect gases which are soluble in water and
heavier than air.
Is an example of gas which is soluble in water and heavier than air.
Is used for filtration inside the funnel.
, and Are used as
measuring apparatus.
is widely used fertilizer.
is an important source of Nitrogen.
is an example of phosphatic fertilizer.
Chemicals added to kill pests are called .
, and are the
types of pesticides.
is used to kill or inhibit growth of unwanted plants.
is used to kill insects.
The people who were the predessors to the modern chemists are known as
.
Transformed metal into gold.
Was also known as elixir of life.
Today alchemy is considered as .

State true or false: (Correct if false)

• Physics deals with substances, their composition and properties.
• Biology has three different branches.
• Chemistry deals with energy.
• Physics doesn’t deal with living orgasms.
• Chemistry has two branches: Botany and Zoology
 • Inorganic chemistry is the study of carbon compounds.
• Carbon compounds are mainly built of oxygen and nitrogen.
• Hard glass tube is called test tube.
• Beaker is used for heating purposes.
• Beaker is available in only one size.
• Flat bottom flasks are used for heating.
• Conical flasks are used for distillations.
• Test tube holder has plastic handle.
• Downward displacement of water method is used to collect soluble gases.
• Downward displacement of air method is used to collect gases that are heavier than air.
• Upward displacement of air method is used to collect gases that are insoluble.
• Pipette has a tap at the bottom.
• In burrette, we have to suck the liquid up to required level.
• Most fertilizers are in liquid format.
• Urea is widely used fertilizer.
• Ammonium Nitrate is an important source of Nitrogen.
• Insecticides kills the unwanted growth of the plants.
• Pesticides are used to protect plants from weed, fungi and insacts.
• Chemicals added to kill pests are called fertilizers.
Answer the following:
How many branches are there in science? Which?
What type of study is included in Physics?
What type of study is included in Chemistry?
What type of study is included in Biology?
What are the branches of Chemistry? What do they include study of?
Why is boiling tube used for special purposes?
How many types of flasks are there? Name them.
Why should we use round bottom flasks for heating?
Why do we have wooden handle in test tube holder?
What is the use of wire gauze?
What are different parts of Bunsen burner?
Why is it necessary to dip lower end of thistle funnel below the solution in the flask while
experimenting?
What are different methods to collect gas in gas jar?
What is the use of funnel?
What are different measuring apparatuses we could use?
Give two examples of use of chemistry in Agriculture.
What is a fertilizer?
How many types (forms) of fertilizers are there? Which?
Give two examples of liquid fertilizers.
What is the use of pesticides?
How many types of pesticides are there? What are they?
Why should we limit the use of pesticides?

Why were alchemists discredited by scientific community?