Analysing Matter

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Analysing matterMatter

Matter is anything that occupies space and has mass.

[edit]Atom, Molecule and Ion

The particles can be atoms, molecules or ions.

Atom Molecule Ion

The atom is the

smallest, indivisible

particle of an element.

Atoms of the same

element are exactlyalike and are different

from the atoms of all

other elements.

Molecules are the smallest

particles of an element or

compound that are made up of

two or more atoms. Ions are

particles that are charged due toloss or gain of electrons.

Ions which are positively

charged are called cations.

Ions which are negatively charged

are called anions.

Example

ExampleExample

Element and Compound

Matter can either exist as an element or a compound.
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[edit]Element

Elements can exist as atom, molecule or ion.

Chemical element is the class of atoms with the same number of protons in the nucleus.

An element consists of only one type of atom.

Element can be either atoms or molecules.

[edit]Compound

Compound can be molecule or ion.
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A compound is any substance composed of identical molecules consisting of atoms of two or

more elements.

A compound is made up of either molecules or ions.

[edit]The particle theory of matter

The particle theory of matter states that matter is made up of a large number of tiny and discrete particles.

[edit]Diffusion

Diffusion

Diffusion is a process resulting from random motion of molecules by which there is a net flow of

matter from a region of high concentration to a region of low concentration.

Diffusion is the movement of particles from higher concentration to lower concentration.

It is a physical process rather than a chemical reaction.

In diffusion, the particles of one substance mingle and move through the particles of another

substance.

The rate of diffusion is proportional to the average velocity of the particles in matter.

Example of diffusion
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[edit]Diffusion in Solid

Before Diffusion After Diffusion

Copper(II) sulphate crystals are made of copper(II) ions and sulphate ions which are

tiny and discrete.

The particles in the copper(II) sulphate crystal will separate to become ions anddiffuse randomly upwards until the whole agar turns blue.

Diffusion of solid is defined operationally as the random movement of particles to all

directions in a solid.
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[edit]Diffusion in Liquid


Diffusion has taken place in the liquid.

The rate of diffusion of the particles in water is faster than the diffusion rate of

particles in solid.

The occurrence of diffusion proves that potassium permanganate(VII) consist of tiny

and discrete particles.

[edit]Diffusion in Gas
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Bromine vapour is made of tiny and discrete molecules that move randomly to fill up

space.

Bromine vapour moves randomly and diffuses in all directions in air from areas of

higher concentration to areas of lower concentration.

Brownian motion

Brownian motion is the physical phenomenon that

minute particles immersed in a fluid move about randomly.

It was named for the Scottish botanist Robert Brown,

the first to study such fluctuations

Brownian movement, an example of diffusion, supports

the kinetic theory of matter.

Examples of Brownian movement are

1. movement of smoke particles in air

2. movement of pollen grains in water

Kinetic Theory of Matter

The characteristics of matter can be described using the kinetic theory of matter.

The kinetic theory of matter explains the state of matter in solid, liquid and gaseous states based

on the following assumptions:

The gas consists of very small particles, each of which has a mass.

These molecules are in constant, random motion. The rapidly moving particles constantly collide

with each other and with the walls of the container.

There are forces of attraction between particles of matter. These attraction forces will increase as

the distance between the particles becomes closer.

The average kinetic energy of the gas particles depends only on the temperature of the system.

The higher the temperature, the higher the kinetic energy of the particles.
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Changes in the state of matter

Characteristic of Matter in Solid, Liquid and Gaseous State

Characte

ristic

Solid Liquid Gas

Image

Arrange

ment of

Particles

Particles are arranged in

an orderly manner and

close to one another.

Particles are not arranged

in order.

The space between

particles is moderately

large. The particles are

very far apart and

randomly arrange.

Moveme

nt of

Particles

Particles vibrate at fixed

positions.

Particles move randomly

and slowly and

sometimes will collide

against each other.

The particles move

randomly in all directions

at great speed.

Force of

Attractio

n

between

particles

very strong Strong but weaker than in

the solid state.

very weak

Ability

to be

compres

sed

Very difficult to be

compressed because the

particles are packed

closely.

Not easily compressed

because the particles are

packed quite closely.

Easily compressed

because the particles are

very far apart.

Volume Fixed Fixed Varied

Heat

Energy

content

Lowest Energy Content Moderate energy content. Highest energy content
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Shape Fixed Follows the container Fills the whole container

The changes in the state of matter

[edit]Melting

Definition Melting is the process where a solid changes to its liquid state at a certain temperature (called

the melting point) and pressure when it is heated.

Notes

When a solid is heated, the particles obtain energy and vibrate at a faster rate.

As the temperature increases, the vibration of the particles increases until they reach the melting

point where the particles obtain enough energy to overcome the forces that hold them in their fixed

positions.The solid then changes into a liquid.

During melting, the temperature remains constant. This is because the heat energy is taken in by

the particles to overcome forces between them instead of being used to raise the temperature.

The freezing and melting points of a pure substance are the same.

[edit]Freezing

Definition Freezing is the process where a liquid changes to its solid state at a certain temperature

(called freezing point) and pressure when it is cooled.

Notes

When a liquid is cooled, the temperature drops as heat energy is released to the surroundings.

As heat energy is released, the kinetic energy of the particles in the liquid decreases, causing a

slower movement of particles.

The particles lose their energy and are pulled closer by the strong forces between the particles.

As the temperature keep on dropping until it reach the freezing point, the liquid start changing into

solid.

The temperature stays constant while the liquid freezes because heat energy is released when

the particles slow down to take up fixed and orderly positions in the solid.
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[edit]Vaporization

Definition Vaporization, also called evaporation is the process whereby atoms or molecules in a liquid

state gain sufficient energy to enter the gaseous state.

Boiling is the rapid vaporization of a liquid at a certain temperature (the boiling point) and pressure when

heat is applied to it.

Notes

[edit]Evaporation

Evaporation occurs below the boiling point of the liquid.

The particles escape from the surface of the liquid to form gas.

Evaporation differs from boiling in that it only takes place at the surface of the liquid and it is very

slow.

On the other hand, boiling takes place throughout the liquid and is very fast.

Factors influencing rate of evaporation

1. Humidity of the air.

2. Temperature of the substance.

3. Flow rate of air.

4. Inter-molecular forces. The stronger the forces keeping the molecules together in the liquid or

solid state the more energy that must be input in order to evaporate them.

If conditions allow the formation of vapour bubbles within a liquid, the vaporization process is

called boiling.

[edit]Boiling

When a liquid is heated, the particles gain energy and move faster. As heat energy is keep on supplying to the liquid, the particles will eventually obtain enough

energy to completely break the forces in between molecule.

The liquid then changes into a gas and particles are now able to move freely and are far apart.

The temperature at which this happens is called the boiling point.
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The temperature remains constant during boiling because heat energy that is absorbed by the particles is

used to break the forces holding them together.

[edit]condensation

Definition Condensation is the process by which a gas or vapor changes to liquid state at certain

temperature and pressure when it is cooled.

Notes

When a gas is cooled, the particles lose kinetic energy.

As a result they move slower and this will cause the forces between them grow stronger.

At this point, the gas changes into liquid.

During condensation, heat is given out to the surroundings.

Condensation can occur at or below the boiling point of the substance

[edit]sublimation

Definition Sublimation is a process of conversion of a substance from the solid to the vapour state

without its becoming liquid.

Notes

Some solids change directly into gas without becoming a liquid.

This process is called sublimation.

When heated, the particles of the solid gain enough energy to break the forces between them and

move freely as a gas.

When cooled, the gas changes straight back to solid.

Examples of substances which sublime are solid carbon dioxide (dry ice), ammonium chloride

and iodine.
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elting Point, Freezing Point and Boiling Point

[edit]Melting Point

Melting Point Melting Point is the temperature at which the solid and liquid forms of a pure substance can

exist in equilibrium.

[edit]Freezing Point

Freezing Point Freezing Point is the temperature at which a liquid becomes a solid.

[edit]Boiling Point

Boiling Point is the temperature at which the pressure exerted by the surroundings upon a liquid is

equalled by the pressure exerted by the vapour of the liquid. Under this condition, addition of heat results

in the transformation of the liquid into its vapour without raising the temperature.

[edit]Physical State and Temperature

The physical state of a substance at a certain temperature and pressure depends on the values of its

melting and boiling points.

A substance is in solid state if it exists at a temperature below its melting point.
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A substance is in liquid state if it exists at a temperature above its melting point but below its

boiling point.

A substance is in gaseous state if it exists at a temperature above its boiling point.

Change in heat and kinetic energy of particles

The change in temperature will influences the kinetic energy or the speed of the motion of the

particles.

When a substance is heated, the kinetic energy of the particles in the substance increases. This

causes the particles to move or vibrate faster.

Likewise, when a substance is cooled, the kinetic energy of the particles in the substance

decreases. This causes the particles to move or vibrate slower.

The kinetic energy of the particles in a substance is directly proportional to the temperature of the

substance.

[edit]The Graph of the Heating Process

Heating Curve of Naphthalene

The graph above shows the heating curve of naphthalene.
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A Naphthalene is in solid state at any temperature below its

melting point.

The particles are very closely packed together in an orderly

manner.

The forces between the particles are very strong. The particles

can only vibrate at a fixed position.

A-

B As the naphthalene is heated, heat energy is converted to

kinetic energy.

Kinetic energy increases and the molecules vibrate faster

about their fixed positions and the temperature increases.

B Naphthalene is in solid state at any temperature below its

melting point.

The particles are very closely packed together in an orderly

manner.

The forces between the particles are very strong. The particles

can only vibrate at a fixed position.

B-

C Naphthalene exists in both solid and liquid states.

The temperature remains constant because the heat that

supplied to naphthalene is used to overcome the forces of

attraction that hold the particles together.

The constant temperature is called the melting point.

The heat energy that absorbed to overcome the intermolecular

forces is named as the latent heat of fusion.

C All the naphthalene has completely melted.

Solid naphthalene has turned into liquid.


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C-

D Naphthalene is in liquid state.

As the liquid naphthalene is heated, the molecules gain more

heat energy and the temperature continues to increase.

The particles move faster and faster because their kinetic

energy is increasing.

D Naphthalene still exists in liquid state.

Naphthalene molecules have received enough energy to

overcome the forces of attraction between the particles in the

liquid.

Some of the naphthalene molecules start to move freely and

liquid naphthalene begin to change into gas.

D-

E Naphthalene exists in both liquid and gaseous states.

The temperature remains unchanged.

The is because the heat energy absorbed is used to overcome

the intermolecular forces between the particles of the liquid rather

than increase the temperature of the liquid.

This constant temperature is the boiling point.

E All the naphthalene has turn into gas.

E-

F The gas particles continue to absorb more energy and move

faster.

The temperature increases as heating continues.


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[edit]The Graph of the Cooling Process

P The substance exists in gaseous state.

The particles have very high energy and are moving randomly.

The intermolecular forces between the particles are very weak

and can be ignored.

P-

Q The substance is in gaseous state.

The particles lose kinetic energy during cooling, the particles

getting closer to each other and the temperature drops.

Q The substance still exists as a gas.

As the molecules are close enough, stronger forces of

attraction result in forming of intermolecular bonds.

The gas begins to condense and become liquid.

Q-

R The process of condensation going on.
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Stronger bonds form as gas changes into liquid.

The substance exists in both gaseous and liquid states.

The temperature remains unchanged.

This is because the energy produced during the formation of

bonds is equal to the heat energy released to the surroundings

during cooling.

This constant temperature is the boiling point.

The heat energy that releases during this condensation

process is called the latent heat of vaporization.

R The substance exists only in liquid state as all the gas particles

have condensed into liquid.

R-

S The substance exists as a liquid.

As the temperature falls, the naphthalene molecules lose heat

energy. Their movement shows down and they move closer to

each other.

S The substance still in liquid state.

The particles have very little energy and begin to move closer

towards one another as it starts to freeze into solid.

S-

T The liquid is changing into solid form.

Molecules rearrange to form the molecular arrangement of a

solid.

The substance exists as both liquid and solid.

The temperature remains constant until all the liquid changes

to solid.

This is because the energy released is the same as the energy


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lost to the surroundings during cooling.

This constant temperature is the freezing point.

The heat energy that releases during this freezing process is

called the latent heat of fusion.

T All the liquid freezes into solid. The particles are now closely

packed in an orderly manner.

T-

U Once all the liquid has become solid, the temperature falls

once again until it reaches room temperature. The substance is in

the solid state here.

U The substance reaches room temperature and remain at this

temperature as long as the room temperature remain the same.

[edit]Supercooling

Super-cooling is the cooling of a liquid to below its freezing point but keeping it in liquid state.

Supercooling is possible because of the lack of solid particles around which crystals can form.

Synthesising atomic structure
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Atomic Structure

In physics, atomic theory is a theory of the nature of matter. It states that all matter is composed

of atoms.

The word atom originally meant a smallest possible particle of matter, not further divisible.

History

[edit]Democritus

The existence of atoms was proposed as early as in the 5th century BCE by the Greek

philosophers Leucippus and his pupil Democritus, for which they were called atomists.

Democritus, develop the idea of atoms. He asked this question: If you break a piece of matter in

half, and then break it in half again, how many breaks will you have to make before you can break it

no further?

Democritus thought that it ended at some point, a smallest possible bit of matter. He called these

basic matter particles, atoms.

The word "atom" is derived from the Greek word "atomos", which means "indivisible".

[edit]John Dalton

Dalton's Model of Atom
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John Dalton

Five main points of Dalton's Atomic Theory

1. All matter is composed of extremely small particles called atoms.

2. All atoms of a given element are identical, having the same size, mass, and chemical properties.

Atoms of a specific element are different from those of any other element.

3. Atoms cannot be created, divided into smaller particles, or destroyed.

4. Different atoms combine in simple whole-number ratios to form compounds.

5. In a chemical reaction, atoms are separated, combined, or rearranged.

Weakness

Atoms consist of even smaller particles called electrons, protons and neutrons.

Atoms can be created and destroyed in the nuclear reactions such as nuclear fusion and nuclear

fission.

Atoms of the same element can have different physical properties, for example, isotopes of

hydrogen.

[edit]J.J. Thomson

JJ Thomson
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In physics, the Plum pudding model of the atom was made after the discovery of the electron and

was proposed by the discoverer of the electron, J. J. Thomson.

In it, the atom is envisioned as electrons surrounded by a soup of positive charge, like plums

surrounded by pudding.

The electrons were positioned uniformly throughout the atom.

Instead of a soup, the model is also said to have had a cloud of positive charge.

This model can be compared to a British treat called plum pudding, hence the name. It is also

known as the chocolate chip cookie model.

[edit]Ernest Rutherford

[edit]Gold foil experiment

The gold foil experiment:Most of the alpha particles penetrated through the gold foil without deflection. The others were

deflected at different angles. Small amount of the alpha particles were reflected back.

The Gold foil experiment, or Geiger-Marsden experiment was an experiment done by Hans Geiger and

Ernest Marsden in 1909, under the direction of Ernest Rutherford at the Physical Laboratories of the

University of Manchester which led to the downfall of the plum pudding model of the atom.
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Expecting result base on plum

pudding modelActual result

They measured the deflection of alpha particles directed normally onto a sheet of very thin gold

foil.

Under the prevailing plum pudding model, the alpha particles should all have been deflected by at

most of a few degrees.

However they observed that a very small percentage of particles were deflected through angles

much larger than 90 degrees.

From this Rutherford concluded that the atom contained a very small positive charge which could

repel the alpha particles if they came close enough.

[edit]Rutherford Atom

Ernest Rutherford

Early in 1911 Rutherford published a revised model of the atom, known as the Rutherford atom.

He concluded that

1. the atom is mostly empty space,

2. most of the atom's mass concentrated in a tiny center, the nucleus and electrons being held inorbit around it by electrostatic attraction.

3. The nucleus was around 10-15 meters in diameter, in the centre of a 10-10 metre diameter atom.

4. Those alpha particles that had come into close proximity with the nucleus had been strongly

deflected whereas the majority had passed at a relatively great distance to it.
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[edit]Niels Bohr

Niels Bohr

Niels Bohr improved on Rutherford's atomic model.

Bohr model depicts the atom as a small, positively charged nucleus surrounded by electrons in

orbit - similar in structure to the solar system, but with electrostatic forces providing attraction, rather

than gravity.

According to Bohrs Model

1. Electrons in an atom of an element are not randomly distributed around the atomic nucleus.

2. Electrons move around the nucleus in fixed orbits.

3. Each orbit forms a circle and has a fixed distance from the nucleus.

[edit]James Chadwick

Chadwick

Chadwick discovered the presence of neutrons in the nucleus.

He concluded that the nucleus contains another tiny particle known as a neutron that has no

charge.
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The neutron mass is almost similar to the proton mass.

All nuclei contain protons and neutrons, except for the hydrogen which contains protons. only

[edit]Modern Atomic Model

The atomic model in the present day is based on the contributions of the above scientists.

According to the modern atomic model,

1. The central nucleus consists of protons and neutrons. It containing almost all the mass of the

atom.

2. the nucleus of an atom is very small compared to the size of the atom

3. the electrons are orbiting outside the nucleus in the electron shells

4. the electrons are moving in electron shells at a very high speed and we cannot determine the

position of the electrons at a particular time

[edit]The subatomic particles of an atom

Atoms are made up of tiny particles called subatomic particles.

An atom contains three types of subatomic particles:

1. proton,

2. neutron and
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3. electron,

The proton and neutron form the nucleus at the centre of an atom.

The electron moves around the nucleus at a very high speed.

The nucleus is positively charged because of the presence of protons, which are positively

charged. The neutrons are neutral.

The symbols, charge and relative masses of proton, neutron and electron are as below.

Partic

le

Symb

ol

Relative

charge

Relative

mass

Proton p +1 1

Neutro

nn 0 1

Electro

ne -1 1/1840

[edit]The charge of particles

A neutral atom contains the same number of electrons as the protons.

The positive and negative charges of the protons and electrons respectively neutralise each

other, for example, +4 + (-4) = 0

If the number of protons is greater than the number of electron, the particle is positively charge.

If the number of protons is greater than the number of electron, the particle is positively charge.

Example

Number of

proton

Number of

electron

Char

ge

3 3 0
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5 2 +3

9 10 -1

11 10 +3

16 18 -2

17 18 -1

20 18 +3

[edit]Proton number and nucleon number

[edit]Proton Number

The proton number (Z) represent the number of protons found in the nucleus of an atom.

Proton number = the number of protons

The proton number is also known as the atomic number.

In an atom of neutral charge, the number of electrons also equals the atomic number.

Hence, the proton number of an atom can also represent the number of electrons.

[edit]Nucleon Number

The nucleon number (A), also called atomic mass number or mass number, is the number of

protons plus the number of neutrons in an atomic nucleus.

Nucleon number = Number of protons + Number of :neutrons

The nucleon number of an atom is about the same as the mass of the atom because the mass of

an electron is very small and can be ignored.

Example

Atom Proton Nucleon Amount of Amount of Amount of
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Number Number Proton electron Neutron

Helium 2 4 2 2 2

Oxygen

8 16 8 8 8

Sodiu

m11 23 11 11 12

Chlorin

e17 35 17 17 18

The structure of an atom can be written in symbol form, as shown in the figure below.

Symbol: X

Proton Number: B

Nucleon Number: A

Symbol: N

Proton Number: 7

Nucleon Number: 14

Symbol: X

Proton Number: B

Nucleon Number: A

IsotopeIsotope

Isotopes are atoms of certain elements which have the same number of protons but different

number of neutrons in the nucleus of the atoms.

It can also can be defined as atoms of certain elements with the same proton numbers but with

different nucleon numbers.

Three important points to define isotopes.

1. Isotopes are different atoms of the same element.

2. Isotopes have the same number of protons or same proton numbers.

3. Isotopes have different numbers of neutrons or nucleon numbers.


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Properties of Isotope

Number of

protonequal

Number of

neutron

differen

ce

Chemical

propertiessame

Physical

properties

differen

ce

Example

Eleme

ntName

Symb

ol

Proton

Number

Nucleon

Number

Number

of proton

Number

of

neutron

Hydrog

en

Hydroge

n1 1 1 0

Deuteriu

m1 12 1 1

Tritium 1 23 1 2

Oxygen

Oxygen-

168 16 8 8

Oxygen-

178 17 8 9

Oxygen-

18 8 18 8 10

Carbon Carbon-

126 12 6 6

Carbon- 6 13 6 7


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13

Carbon-

146 14 6 8

Chlorin

e

Chlorine-

3517 35 17 18

Chlorine-

3717 37 17 20

Sodium

Sodium-

2311 23 11 12

Sodium-24 11 24 11 13

[edit]Uses of isotopes in our daily lives

There are two types of isotopes, namely

1. the stable isotopes (non-radioactive)

2. the non-stable isotopes (radioactive).

Unstable isotopes go through radioactive decay and emit radiation and they are known as

radioisotopes.

Radioisotopes have many applications in daily life.

Several uses of radioisotopes in daily life are shown in Table below.

[edit]Medical

Gamma rays of cobalt-60 are used to kill cancer cells without surgery in patients. This treatment

is known as radiotherapy.

Patients with skin cancer can be treated using beta rays from the isotopes phosphorus-32 and

strontium-90

Medical instruments such as surgical equipment, syringes and bandages can sterilize by using

gamma rays.
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Radioisotopes are also used as tracers.

A small amount of sodium-24 is injected into the patient's body.

A radioactive detector is then used to detect accumulation of sodium-24 and therefore detect

tumours and blood clots before they become dangerous.

This tracing method is also used to investigate the thyroid glands by measuring the uptake

of iodine-131.

Plutonium-238 in a nuclear battery is used to produce small electric shocks in the heart

pacemaker.

People with irregular heartbeats need to have a heart pacemaker implanted inside their chest.

The nuclear battery of the pacemaker provides a tiny electrical shock to ensure a steady

heartbeat.

[edit]Agricultural

Radio isotopes are used to cause mutation in insects so as to make them sterile

or to cause death. These serve as pest control in agriculture.

The metabolism of phosphorus by plants can be studied using phosphate

fertilisers that contain phosphorus-32.

A small amount of phosphorus-32 is used in fertilisers.

The radiation produced by phosphorus-32decaying is detected by a Geiger-Miller counter.

This method can trace the passage of phosphate ions in plants..

Carbon-14 is used to study the passage of carbon during

photosynthesis in plants.

[edit]Industrial

Isotope sodium-24 is used to detect leakage of underground

pipes.

Beta rays are used to control the thickness of plastic, paper and

metal sheets in factory.
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Gamma rays are used to detect whether cans or bottles are

filled up to the required amount.

Sodium-24 is used to measure the wear out rate of engine in a

vehicle.

[edit]Food Preservation

The gamma rays from cobalt-60 are used to kill bacteria in food

to make fresh vegetables and fruits last longer without any

change in quality, flavour and texture of food.

Gamma rays are used to inhibit budding in potatoes.

[edit]Archeology

Radioisotope carbon-14 is used to study and estimate the age

of ancient artifacts. This method is named as the radiocarbon

dating.

[edit]Production of Energy

Plutonium is used in nuclear reactors to produce electrical

energy.

[edit]Danger of Radioactive

Radioactive isotopes are very dangerous if it is misused.

Short-term exposure to radioactive rays may

1. kill or destroy the cells in our body and cause organ

damage

2. cause rashes and burns on the exposed skin

Long-term exposure to radioactive rays may
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1. ause mutation in our genes and abnormalities in newborn

babies

2. disturb the growth and division of cells and consequently

cause cancer

3. Electronic Structure

Electron Configuration in Atom

We have learnt that electrons occupy orbits with definite energy level of an atom, as suggested

by Neils Bohr.

These orbits with definite energy level are known as the shell.

Every single shell is capable of holding up to certain amount of electrons.

The first shell can hold up to two electrons. This is called a duplet.

The second shell can hold up to eight electrons. This is called an octet.

The third shell can hold up to eighteen electrons.

However, with the third shell, when eight electrons are present, extra stability is gained. The

additional electrons go into the fourth shell before the third shell is completely filled.

The way in which the electrons are distributed in the shells of an atom is called the electron

arrangement or electron configuration of the atom.

The examples below show the electron arrangement of some elements:

Example

Atom Notes

Electrons

Arrangemen

t

Lithium has 3 protons

and 3 neutrons and three

electrons as well.

All the three electrons

are arrange as follows:

2.1
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1. Two electrons are

filled in the first shell.

2. One electron is filled

in the second shell.

3. The electron

arrangement of

carbon is 2.1

Chlorine has 17

protons and 18 neutrons

and 17 electrons.





2. Eight electrons are

filled in the second

shell.

3. Seven electrons are

filled in the third

shell.

4. The electron

arrangement of

chlorine is 2.8.7.

2.8.7
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Calcium has 20

protons and 20 neutrons

and 20 electrons.






filled in the second

shell.


filled in the third

shell.


filled in the forth

shell.

5. The electron

arrangement of

carbon is 2.8.8.2.

2.8.8.2

ElementProton

Number

Number of

Electron

Number of electron in

Electron

Arrangement1st

shell

2nd

shell

3rd

shell

4th

shell

Hydrogen 1 1 1 0 0 0 1

Helium 2 2 2 0 0 0 2

Lithium 3 3 2 1 0 0 2.1

Beryllium 4 4 2 2 0 0 2.2

Boron 5 5 2 3 0 0 2.3
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Carbon 6 6 2 4 0 0 2.4

Nitrogen 7 7 2 5 0 0 2.5

Oxygen 8 8 2 6 0 0 2.6

Fluorine 9 9 2 7 0 0 2.7

Neon 10 10 2 8 0 0 2.8

Sodium 11 11 2 8 1 0 2.8.1

Magnesiu

m12 12 2 8 2 0 2.8.2

Aluminium

13 13 2 8 3 0 2.8.3

Silicon 14 14 2 8 4 0 2.8.4

Phosphor

us15 15 2 8 5 0 2.8.5

Sulphur 16 16 2 8 6 0 2.8.6

Chlorine 17 17 2 8 7 0 2.8.7

Argon 18 18 2 8 8 0 2.8.8

Potassium 19 19 2 8 8 1 2.8.8.1

Calcium 20 20 2 8 8 2 2.8.8.2

Documents

Analysing Matter