chapter 4 student copy

7/31/2019 CHAPTER 4 Student Copy

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Science Form4 || Miss Erina

CHAPTER 4 : MATTER AND SUBSTANCE

KINETIC THEORY OF MATTER

- Matter is made up of very fine and discrete particles- The particle of matter constantly move or vibrate- The particle constantly collide against one another and the walls

of the container

- Forces of attraction exist among the particles in matter. theforces of attraction becomes stronger when the particles are

packed closely together.

- The higher the temperature,the higher the kinetic energy of theparticles

Diffusion : movement of particles in matter from an area of

_______concentration to an area of ______ concentration until both

areas have the same concentration.

The particles of liquid and gase move randomly and collide against one

another.this movement is called B___________ movement.

Temperature influences the kinetic energy content of matter. (higher

Temperature,higher kinetic energy of the particles)

PROPERTIES OF MATTER

PROPERTY OF

MATTER

SOLID LIQUID GAS

ARRANGEMET OF

PARTICLE

-particles are

arranged

closely,compactly

and orderly in fixed

positions

-very little empty

space between one

particle and another

-not nearly nor

closely arranged

-they are empty

spaces among

particles

-most of the particles

keep contact with

one another

-not nearly arranged

and are further apart

from one another.

MOVEMENT OF

PARTICLES

Do not move

freely,only vibrate at

their fixed positions

Move slowly in a

random manner

Move fast in a

random manner and

in all direction

FORCES OF

ATTRACTION

BETWEEN

PARTICLES

ENERGY CONTENT moderate

SHAPE fixed Following shape of

container

Not fixed

VOLUME fixed fixed Not fixed

COMPRESSION Very difficult to

compress

Properties of matter in solid,liquid and gaseous state.


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CHANGES IN THE STATE OF MATTER

-HEAT is the energy that determine the movement of particles in matter.

-if the temperature of matter increases,particles will get higher kinetic

energy to move faster

-changes in the state of matter occur through the process of heating or

cooling,( when energy is absorbed or released from the matter)

-when heat is applied,state of matter will change from solid to liquid to

gas.

Melting boiling sublimation

-when heat is released,state of matter will change from gas to liquid to

solid

Freezing condensationsublimation

SUBLIMATION = occurs when the state of matter changes from solid to

gas or vice versa without going through the liquid stage.

-changes in the state of matter can be explained graphically

STAGE AB:

(a) at A,the substance is in a_______ state

(b) at AB,energy is absorbed by particles when heated. Temperature of

the substances rises and kinetic energy __________

STAGE BC:

(c) at B, substance still in solid state.the energy absorbed by the particles

is sufficient to __________ the forces of attraction between particles.

Solid begins to ______

(d) at BC, the substance is in a _________ state. Temperature does not

rise even though heating continues.

Heat enerfy supplies is used to overcome forces of attraction between

particles.this results in the change of state from solid to liquid. The

constant temperature is calles melting point

STAGE CD:

(e) at C,the substance is in _______ state

(f) at CD, heating is continued.the temperature rises causing the particles

to obtain more energy and move faster as their kinetic energy has

_________ causing the temperature to rise.

STAGE DE:

(g) at D,substance is in a liquid state. Energy absorbed by the particles issufficient to overcome the forces of attraction between particles. The

particles move freely to form gas.


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(h) at DE,the substance is in a ______________ state. The heat energy

supplied is used to overcome the forces of attraction between liquid

particles to become gas. The constant temperature is called ___________

STAGE EF:

(i) at E,substance is in ___________ state

(j) at EF,the particle continue to absorb heat and move faster. Their

temperature comtinue to rise.

- if a substance is cooled,the changes in the state of matter can also be

explained graphically.

STAGE PQ:

(a) at P,the substance is in a ________state and the particle is move

freely.

(b) at PQ,the particles loss ________ energy and temperature falls when

cooled

STAGE QR:

(c) at Q,the substance is still in a __________ state. The forces of

attraction formed among the particls. The gas begins to condense to form

_________

(d) at QR, the substance is in a gaseous-liquid state. The forces of

attraction between particle that change gas to liquid causes the release of

energy. The constant temperature is called boiling point.

STAGE RS :

(e) at R,the substance is in a ______ state

(f) at RS, the temperature falls and the particles begins to release energy

and move increasingly slower when cooled.

STAGE ST :

(g) at S,the liquid begins to _______ and the particles are arranged closely

to each other and in an orderly arrangement.

(h) at ST, the substance is in a _____________ state. The particles

continue to release energy and are held together by strong forces of

attraction between them. The temperature at this stage is constant and is

called _______________

STAGE TU :

(i) at T,all liquid is in a ________ state. The particles are closely and

uniformly arranged.

(j)at TU,the temperature of the solid keeps going down when cooling is

continued.


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STRUCTURE OF ATOM

1. all matter consists of tiny units called atoms.

2.atom is a basic unit of all matter

3. atoms cannot be seen with an ordinary microscope because they aretoo tiny

4.an atom consists of a nucleus in the centre surrounded by

electrons.electrons move around the nucleus fo llowing a certain orbit.

SUBATOMIC PARTICLES

- An atom is made up of particles that are even smaller calledsubatomic particles

- There are three type of subatomic particles which are:1. __________ 2.____________ 3.____________

- protons and neutrons form the nucleus in the centre of an atom

- Electrons move around the nucleus at high speed

-the mass of an atom is concentrated in its nucleus.

-atoms of any element are neutral because the number of protons and

the number of electrons in an atom are the same

- in a neutral atom, the total positive charges in the nucleus are the same

as the total negative charges from the electrons which orbit around the

nucleus.

Number of protons = number of electrons

OR

Number or positive charges = number of negative charges.

- Ions are atoms or particles which have charge. Ions are producedwhen the _______________ (positive charge) and the

______________ (negative charge) are not balanced

- Positive ions = particles that are positively charged (producedwhen the number of protons is more than the number of

electrons)- Negative ions = particle that are negatively charged. (producedwhen the number of electrons is more than the number of

protons.)

PROTON NUMBER AND NUCLEON NUMBER

PROTON NUMBER = NUMBER OF PROTONS in an atom of anelement.

Elements can be differentiate by referring to their proton number In a neutral atom,the proton number also refers to the number of

electrons in that atom.

NUCLEON NUMBER : total number of protons and neutrons in anatom of an element.

NUMBER OF NEUTRONS = can be calculated if its proton numberand nucleon number are known.


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In a neutral atom :Nucleon number = no.of electrons + no.of neutrons

= nucleon number no.of protons

ISOTOPES

Atoms of the same element that possess the same______________but different ______________

OR

Atoms of the same element with the same proton number butdifferent nucleon number.

Isotopes of the same elements possess the same chemicalproperties.

The physical properties of isotopes are different.CLASSIFICATION OF ELEMENTS IN THE PERIODIC TABLE

In Periodic Table,the elements are arranged in order of increasingproton number.(proton number increases from left to right and

from top to bottom)

Vertical column = _______ Elements in same group have similar chemical properties Horizontal row = _________ Chemical and physical properties of elements are gradually

changed when crossing periods

There are ___ groups and ____ periods. Group 1 (alkali metals) and Group 2 (earth alkali metals) consists

of reactive metals Group 17 = non metals (halogens) Group 18 = noble (inert) gases which are chemically stable and

unreactive.

Elements located between Groups 2 and 13 are transitionelements

Most transition elements are hard and shiny. All transitionelements are good conductors of electricity (show metal

properties)

In Period 6,elements numbered from 58 to 71 = Lanthanideseries.

In Period 7,elements numbered from 90 to 103 = Actinide seriesLOCATION OF METALS,NON-METALS AND SEMI-METALS

Most elements in Periodic table are metals.(Group 1,2,13 andtransition metals)

Most non-metals elements are located in Group 16,17,and 18 Seven metals between metals and non-metals are semi-metals .

semi metals possess certain properties of metals and non-metals

Examples of semi metals = boron,silicon,and antimony When moving across a period from left to right, peoperties of

metals change gradually to those of semi-metals and finally tonon-metal.

IMPORTANCE OF THE PERIODIC TABLE

- Study elements in an orderly and systematic approach- Helps us to know the properties of elements easily because

elements with similar properties are located in same group

- Help to predict the properties and uses of an elements.PROPERTIES OF SUBSTANCES BASED ON THEIR PARTICLE

CONTENT

3 types of molecules1. atoms 2.molecules 3.ions


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ATOMS = the tiniest particle in an element

MOLECULES = groups of atoms joined together. A molecule consists of

two or more atoms

IONS = particle which carry positive or negative charges.

ATOMIC SUBSTANCES

Substance that consists of only ______ All metals are atomic substance.(example: iron,lead,sodium) Atoms in atomic substances are packed closely,compactly and

arranged orderly in fixed positions

Atoms are held together by a strong chemical bond

MOLECULAR SUBSTANCE

Molecules are the simplest particles found in molecularsubstance.

Ex: nitrogen,sulphur dioxide and iodine Made up of molecules which have __________ atoms of the

same type (2 oxygen atoms combine to form one oxygen

molecule)

Can also made up of two or more atoms of different types (1nitrogen atom combine with 3 hydrogen atoms to form 1

ammonia molecule)

Molecules are made up of non-metal atoms held together by astrong ___________

Forces attraction between molecules in a molecular substanceare relatively weak. (Van der Waals forces)

IONIC SUBSTANCES

Formed when atoms of ________ combined with atoms of_________ through chemical bonding to form compounds

Ex: sodium chloride,lead(II) bromide When sodium(metal) reacts with chlorine (gas) to form a

compound, the sodium atom will lose an electron to form the

positive ion,Na+

Chlorine atoms will receive the electron to form the negativeion,Cl-

Positive ion and negative ion attract one another . (electrostaticforce)

PROPERTIES AND USES OF METALS AND NON-METALS

METALS = ex: iron,aluminium,zinc,copper,lead,tin,and gold

= all metals exist in a solid state at room temperature

except mercury(liquid)

NON-METALS =

carbon,iodine,bromine,sulphur,phosphorus,chlorine


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-non metals exist in a solid,liquid or gaseous state at room

temperature

- Metals and non-metals possess different physical propertiesLUMINOSITY = shiny appearance

DUCTILITY= substances that are ductile can be stretched out like a

long wire

MALLEABILITY = substances are malleable ,they can be hammered or

rolled into a thin sheet

TENSILE STRENGTH = ability of a substance to support pressure or

load

ELECTRICAL AND HEAT CONDUCTIVITY = ability to let electricity flow

through and to transfer heat.

METALS NON-METALS

Shiny surface Dull surfaces

Ductile Not ductile

Not malleable

High tensile strength Low tensile strength

Good conductor of electricity Do not conduct electricity

except carbon

Good conductor of heat Poor conductor of heat (heat

insulator)

melting point melting point and boiling

point

density density

at room temperature

except mercury

Solid,iquid or gas at room

temperature

USES OF METALS AND NON-METALS IN DAILY LIFE

METAL PHYSICAL PROPERTIES USE

IRON High tensile strength Railway tracks and

framework forbridges

ALUMINIUM Light weight

Good conductor of

electricity and heat

Kitchen

utensils,food

wrapper and

electric cables

COPPER Ductile and malleable

Good conductor of

electricity and heat

Electrical wire

TIN Does not rust Electroplating of

food cans

GOLD Does not rust and shiny JewelleryLEAD Ductile

malleable

Cable casing

NON-METALS PHYSICAL POPERTIES USE

CARBON (GRAPHITE) Soft and smooth

Good conductor of

electricity

Lead of pencils

Electrodes in

electrolysis and in dry

cells

CARBON (DIAMOND) hard Drill bits for cutting

stoneNEON GAS AND

KRYPTON

Poor conductor of

heat

Light uses for

billboards

CHLORINE acidic Kills germs in drinking

water


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METHODS OF SUBSTANCE PURIFICATION

Pure substance do not contain any __________ Pure substance always have specific melting(freezing) point and

boiling point.

Impurities can be separated from pure substances = purification 2 methods of purification :-

1.____________ 2. _________________

DISTILLATION

Used to obtain pure liquid from a solution which containsimpurities

Used to separate 2 liquids mixture that :- __________ one another- Do not _________- Possess _________________ Distillation involves process of heating liquid until it become

vapour (gas). This vapour then condenses to become pure liquid.

Examples :- Breaking crude petroleum into its fractions in a petroleum

fractional distillation tower to produce fuels and to make various

kinds of plastic material

- Production of pure oxygen for use as rocket fuel and oxygensupply for oxygen tanks

- Production of pure water or distilled water for use in thepreparation of chemical solutions in laboratories or medicine in

hospitals ,food industries- Obtaining pure ethanol from fermentation of sugar solution and

yeast.

Can be conducted to separate mixtures of substance such aspurifying alcohol from a mixture of alcohol and water and also

purifying water from a mixture of water and salt.

The substance with a lower boiling point _____ and _________earlier . then the gas (vapour ) will go through condensation toform the pure conduct of distillation.

CRYSTALLISATION

Purification method carried put to obtain pure crystals from asaturated solution of the substance.

Ex: purification of salt from its saturated solution SATURATED SOLUTION = solution containing maximum quantity

of ____________

Examples:- Production of salt from sea water- Preparation of white sugar crystals from sugarcane juice.

EXISTENCE AND USES OF VARIOUS PROPERTIES OF SUBSTANCES

Property of _________ enables metals like copper and aluminiumto be stretched and become wire

Property of ____________enable utensils like knife,pot,spoonand fork to be made or forged

Electrical conductivity of some metals enables electrical wire tobe made

Tensile strength of metals enables bridges to be built Nitrogeneous compound which easily dissolves in water is used to

make fertiliser.

chapter 4 student copy

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