CHAPTER 4 : MATTER AND SUBSTANCE1. Matter : Anything that has and .

STATES OF MATTERSOLID

LIQUID

GAS

Arrangement of particles.packed in an .. arrangement closely packed, .. in an orderly arrangement , .. far apart , in an orderly arrangement ,

Movement of particlesVIbrate.and rotate in a fixed positionMove freely..Move freely.and rapidly..

Forces of attraction strong.. strongVery .

Kinetic energy of particlesVery lowmoderateVery high

DensityVery highmoderateVery low

CHANGES IN STATES OF MATTERProcessChange of stateFactor

MeltingSolid LiquidHeatingHeat is absorbed

Boiling/ evaporationLiquid GasHeatingHeat is absorbed

FreezingLiquid SolidCoolingHeat is released

CondensationGas LiquidCoolingHeat is released

SublimationSolid GasHeatingHeat is absorbed

SublimationGas SolidCoolingHeat is released

ExerciseState whether the processes below released or absorbed heat energy? (a) boiling: .. (b) sublimation: (c) condensation: .2. State the change in the state of matter that occurs during the following process: (a) melting : . (b) boiling : .. (c) freezing : . ExperimentAim :To study the changes in the states of matterMaterials : and apparatus : Ice cubes, thermometer, 50 mf beaker, wire gauze, Bunsen burner, tripod stand

1. Set up the apparatus as shown in the diagram.2. Heat the ice cubes slowly.3. Record the temperature reading every two minutes until the water boils.Results :

Time ( min)0246810121416

Temperature ( )

Discussiona) Based on the results of this activity, draw a graph of the temperature against time.b) Based on the graph in 1, state the relationship between the temperature and time after the ice melts and before the water boils.

c) Predict the temperature of the water at the 21st minute.Conclusion : The ice and the water when heated3. A student carried out an experiment to determine the boiling point of a solution. The table below shows the result of the experiment.

Time / minute0246810

Temperature / oC28486888102102

(a) Based on the table above, draw a graph of temperature against time.

(b) What is the relationship between the temperature of the solution and time in the first 6 minutes? (c) Based on the graph in (a), determine the boiling point of the solution. Mark the boiling point of the solution on the graph. Boiling point = The structure of atomsAtom is a small , indivisible particle

Discover electron

Discover proton

Discover neutron neutron

Discover orbit

JOHN DALTONJ.J THOMSONERNEST RUTHERFORDJAMES CHADWICKNIELS BOHR

ActivityMatch the name with the correct descriptionNAMEDESCRIPTION

J.J thomson

[A] Discover proton

Ernest Rutherford

[B] Atom is a small , indivisible particle

James chadwick

[C] Discover electron

John dalton

[D] Discover neutron.

Niels Bohr

[E] Discover orbit

THREE SUBATOMIC PARTICLES

AtomNumber of electrons = number of protonsEg : number of electrons = 2 Number of protons= .neutronprotonelectron

PROTON NUMBER AND NUCLEON NUMBERNUCLEON NUMBER :

PROTON NUMBER :

Number of protons :Number of electrons :Number of neutrons :

Draw the structure of atom of oxygen -16

Complete the tableElementNumber of protonsNumber of neutronsNumber of electronsProton numberNucleon numberSymbol of element

Hydrogen10

Helium22

Lithium34

Carbon66

Nitrogen77

Fluorine910

IONS POSITIVE ION : atom which loses electrons

Number of protons : 11 +Number of electrons : 10- +1 protons > electrons Na+

NEGATIVE ION : atom which receives more electrons

Number of protons : 8 +Number of electrons : 10- -2 protons < electrons O2-

Deduce the numbers of protons, electrons and neutrons in the following atoms:(a) Atom X with proton number 17 and nucleon number 35(b) Magnesium atom with proton number 12 and nucleon number 24

ISOTOPESAtoms of the same element that have the same number of protons but different number of neutrons

Chemical properties= samePhysical properties=different

Examples of isotopesElementIsotopesProton numberNucleon numberNumber of neutrons

HydrogenHydrogen-111

Hydrogen-212

Hydrogen-313

CarbonCarbon-12612

Carbon-13613

Carbon-14614

OxygenOxygen-16816

Oxygen-17817

Oxygen-18818

UraniumUranium-23592235

Uranium-23892238

EXERCISE1. Name three subatomic particles in an atom.Subatomic particles

2. What are the subatomic particles inside the nucleus of an atom? .........................................................................................................................................3. State the charge of (a) protons: .. (b) electrons: ... (c) neutrons: 4. ParticleNumber of protonsNumber of electronsNumber of neutrons

K327

L81016

M131314

Based on the table above, identify (a) neutral atom: (b) positive ion : (c) negative ion : .

5. (a) Complete the table below.ParticleNumber of protonsNumber of electronsNumber of neutrons

V77

W89

X910

Y78

Z1011

(b) What are the proton number and nucleon number of element Z? (i) proton number : (ii) nucleon number : .. (c) (i) Identify a pair of isotopes from the table above? (ii) State an inference for your answer in (c)(i). ..

6. Complete the number of subatomic particles for isotopes of carbon.ElementIsotopeNumber of protonsNumber of electronsNumber of neutrons

CarbonCarbon-12 C

Carbon-14C8

7. Figure below shows the structure of the lithium atom.

proton neutronnucleus electron orbit

What are the proton number and nucleon number of lithium?Proton numberNucleon number

The table below shows the subatomic particles of some element.ElementPQR

Proton number668

Nucleon number14

Number of electrons

Number of neutrons710

(a) Complete the table above.(b) Which of the elements is an isotope ?(c) Define what isotopes are ?

Extra notesa) Atoms and ions

b) Isotopes : Eg : carbon-12 and carbon-13

THE CLASSIFICATION OF ELEMENTS IN THE PERIODIC TABLE

Elements are arranged in increasing . Divided into , .. and GROUPS : vertical column of elements PERIOD: horizontal row of elements Elements of the same group will have :a) same . b) different

Exercise1. Study the periodic table below.

(a) What are represented by the following numbers in the periodic table? (i) 1 18 in vertical column (ii) 1 7 in horizontal column (iii) 1 113 in element symbols (b) How are elements arranged in the periodic table? . (c) What similarities are shown by elements in the same groups? .. (d) Identify the group of elements that (i) is most reactive : (ii) consists of halogens: . (iii) consists of noble gases: 2. The diagram below shows the top half of the Periodic Table. The letters used are not chemical symbols.

K

AFHL

IM

BCDEJN

Write True or False in the space provided for the following statements regarding the Periodic Table above. (a) Elements in the Periodic Table are arranged in decreasing proton number. [.] (b) A and B are elements in the same group. [.] (c) Elements C, D and E are transition elements. [.] (d) Element F is carbon. [.] (e) Elements K, L, M and N are in group 17. [.] (f) Elements H, I and J have the same chemical properties. []3 Explain how elements in the Periodic Table are arranged.

4 Figure 4.19 shows a Periodic Table.

(a) Name an element which is in (i) Group 1: (ii) Period 5 :(b) Which two elements have similar chemical properties? Why?

(c) Which element is a (i) metal? : (ii) non-metal?: (iii) semi-metal?:(d) State the proton number for atom: (i) A : (ii) E : (e) Draw a Periodic Table and label the locations of metals, non-metals and semimetals.

THE PROPERTIES OF SUBSTANCES

Substances made of atoms

Substances made of molecules

Substances made of ions

High melting and boiling points ( metals)-The atoms are held together by strong metallic bonds-More heat energy is needed to overcome the forces of attraction

Low melting and boiling points ( noble gases )-The molecules are held together by weak Van der Waals forces-Less heat energy is needed to overcome the forces of attraction

Low melting and boiling points-The molecules are held together by weak Van der Waals forces-Less heat energy is needed to overcome the forces of attraction

High melting and boiling points -the ions are held together by strong electrostatic force -More heat energy is needed to overcome the forces of attraction

Able to conduct electricity in both molten and solid states There are electrons which can move freely within the metal to conduct electricity

Cannot conduct electricity There are no charged particles in themDo not conduct electricity in their solid state -In a solid state, ions are held in a fixed position and cannot move freely Conduct electricity in molten or solution -The ions can move freely

Physical state-solid ( for all metals except mercury)-Gas ( for all noble gases)Physical state-solid , liquid and gasPhysical state-solid

Melting and boiling pointProcedure1. Set up the apparatus as shown in diagram2. Heat the lead powder in the crucible strongly until it melts.3. Record the melting point of the lead 4. Repeat steps 1 and 2 by using sulphur powder and lead bromine powder.

Result

Electrical conductivity

Procedure1. Set up the apparatus as shown in diagram2. Switch on the circuit and observe whether the bulb lights up or not.3. Then switch off the circuit and heat the lead strongly until it melts. Switch on the circuit and observe whether the bulb lights up or not again.4. Steps 1 to 3 are repeated using sulphur powder and lead bromide powder.

SubstanceObservation (does the bulb light up or not)Inference

LeadSolidYesConducts electricity in both solid and molten states

LiquidYes

SulphurSolidNoCannot conduct electricity

LiquidNo

Lead bromideSolidNoOnly conducts electricity in molten state

LiquidYes

Activity

Oxygen, sodium oxide, carbon dioxide, copper sulphate, hydrogen, magnesium, water, lithium, helium, lead, iron oxide

Which of the substances in the above list are made of(a) atoms?(b) molecules?(c) ions?The physical properties of substances L, M and N are stated below.SubstanceLMN

Melting pointHighHighLow

Electrical conductivityYesOnly in molten state or when dissolved in waterNo

Which of the substances could be(a) sulphur?(b) iron?(c) lead chloride?Give reasons for your answers in (a), (b) and (c).

Why can substances made of ions conduct electricity when melted or dissolved in water, but are unable to do so in the solid state?

METALS AND NON-METALSElements

Non-MetalsEg: oxygen, nitrogen,carbon, sulphur,chlorine, argon,bromine, iodine,

MetalsEg: Iron, magnesium,Lead, gold,copper, mercury,sodium, tin,

The properties of

MetalsNon-metals

Shiny surface (luminous) Malleable and ductile High density High tensile strength Good thermal conductor Good electrical conductor High melting and boiling points Dull surface Brittle and non-ductile Low density Low tensile strength Poor thermal conductor Poor electrical conductor Low melting and boiling points

Ductile - Can be drawn into wires / can be stretched Malleable - Can be bent or shaped without breaking Brittle Hard but breaks easily Tensile strength - Ability of an object to bear weight or tension without breaking

Observation

Non-metalNon-metal

LuminosityThe surface of a copper rod and a carbon rod are rubbed with a piece of sandpaper.

The surface of the copper rod becomes shiny.

The surface of the carbon rod remains dull.

Ductility and tensile strength1. The length of a copper rod is measured.2. The apparatus as shown in diagram below is set up. One end of the copper rod is pulled to determine whether it becomes longer and thinner.3. The length of the copper rod is measured again.4. Then, it is pulled harder to determine whether it can snap easily or not.5. Steps 1 to 4 are repeated using carbon rod.

The copper rod becomes longer and thinner. It does not snap when a greater force is applied.The carbon rod cannot be pulled to become longer and thinner. It snaps easily when a greater force is applied.

Malleability1. A strip of copper wire is bent to form a circle2. Step 1 is repeated using a pencil lead

The copper wire can be bent easily.The pencil lead cannot be bent. It breaks easily.

Electrical conductivity 1. The apparatus as shown in diagram below is set up.2. Both ends of an iron rod are connected to the crocodile clips to complete the circuit. The bulb is observed to determine whether it lights up or not.3. Steps 1 and 2 are repeated using a block of sulphur.

The bulb lights up. This shows that iron conducts electricity.The bulb does not light up. This shows that sulphur does conduct electricity.

Heat conductivity1. One end of an iron rod and a carbon rod are dipped into a beaker of hot water as shown in diagram A 2. The rods are left in the hot water for 10 minutes.3. The other ends of the rods are tested by hand to find out whether they are hot or not as shown in diagram B

The iron rod is hot.The carbon rod is not hot.

Differences between metals and non-metalsMetalsIn terms ofNon-metals

Luminosity

Density

Melting and boiling point

Ductility

Malleability

Tensile strength

Electrical conductivity

Heat conductivity

Uses of metals

MetalPropertiesUses

Copper Excellent conductor of heat and electricity Highly ductile and malleable Making electrical wires and water Making kitchen utensils Copper tooling and statues

Aluminium Low density Ductile and malleable Good heat and electrical conducts Making cooking utensils Making soft drink cans Making the bodies of aircrafts Making electrical cables

Iron Malleable and ductile High tensile strength Building vehicles and machines Used as building material for buildings, bri railway tracks Making stainless steel

Tin Malleable and ductile Corrosion resistant Making tin-plated cans Making pewter

Lead Malleable and ductile Good conductor of electricity Making electrodes of car batteries Storage containers for radioactive substana

Zinc Malleable and ductile Good electrical conductor Corrosion resist Making casings of dry cells Making galvanised iron as roofing material

Gold and silver Shiny Corrosion resistant (SPM) Malleable Making jewellery Making decorative items

Uses of non- metals

Non-metalPropertiesUses

Chlorine Poisonous Dissolves easily in water to form acids Can make things turn pale or white As a disinfectant to kill germs in swimming pools and water treatment plants Making organic solvents Making plastics As a bleaching agent in making detergent

Neon Non-reactive Making advertising lamps and electronic appliance

Helium Non-reactive Low density Used to fill up weather balloons

Carbon in the form of diamond Strong and hard Making jewellery Cutting glass and stones (spm)

Carbon in the form of graphite Soft and flaky Conducts electricity Making pencil lead As electrodes in dry cells As a lubricant in machines

Sulphur Reacts easily with oxygen to form acidic compounds

Making electrolytes in car batteries Making detergents, paints, dyes and fertilisers Making vulcanised rubber

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