Chemistry - F3 to F4 Summer Assignments

7/28/2019 Chemistry - F3 to F4 Summer Assignments

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Summer assignment and revision notes / F3 to F4 Chemistry

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Christian Alliance S C Chan Memorial College

F3 to F4 Chemistry

Summer Assignment and Revision Notes

Name : ( ) Grade :

Class : F.4 ( ) Group : 4X / 4Y / 4Z

Welcome! You will be studying Chemistry in the coming three years. Here are some summer

assignments that you need to complete during this summer vacation.

Part 1 References : NSS Chemistry Curriculum (Secondary 4 6)

Part 2 Revision : Fundamental knowledge in Chemistry. ( Ch 1, 5-8 )

A quiz will be held in early September, 2011.

Part 3 Exercises : Q.1 to Q.9 covering Chapters 5 to 8 of Book 1B. You should hand-in this

assignment on 1 September, 2011.

Part 1 Reference : Chemistry Curriculum (Secondary 4 -6)

A. Compulsory Part

Topic Content

1 Planet Earth ( Book 1A)

1.1The atmosphere1.2The ocean1.3Rocks and minerals

F6

2 Microscopic World I ( Book 1B )

2.1 Atomic structure

2.2 Periodic Table

2.3 Metallic bonding

2.4 Structures and properties of metals

2.5 Ionic and covalent bond

2.6 Structures and properties of giant ionic substances

2.7 Structures and properties of simple molecular substances

2.8 Structures and properties of giant covalent structure

2.9 comparison of structures and properties of important types of substances

F3

and

F4


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3 Metals ( Book 1C )

3.1 Occurrence and extraction of metals

3.2 Reactivity of metals

3.3 Reacting masses

3.4 Corrosion of metals and their protection

F4

4 Acids and Alkalis ( Book 2)

4.1 Introduction to acids and alkalis

4.2 Indicators and pH

4.3 Strength of acids and alkalis

4.4 Neutralisation and salts

4.5 Concentration of solutions

4.6 Volumetric work involving acids and alkalis

F4

5 Fossil Fuels and Carbon Compounds ( Book 2 )

5.1 Hydrocarbon from fossil fuels

5.2 Homologous series, structural formulae and naming of carbon compounds

5.3 Alkanes and alkenes

5.4 Addition polymers

F4

6. Microscopic world II ( Book 3 )

6.1 Bond polarity

6.2 Intermolecular forces

6.3 Structures and properties of molecular crystals

6.4 Simple molecular substances with non-octet structures

6.5 shapes of simple molecules

F4

7 Redox reactions, chemical Cells and electrolysis ( Book 3 )

7.1 Chemical cells in daily life

7.2 Reactions in simple chemical cells

7.3 Redox reactions

7.4 Redox reaction in chemical cells

7.5 Electrolysis

7.6 Importance of redox reactions in modern way of living

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and

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8. Energy changes in chemical reactions ( Book 3 )

8.1 Energy changes in chemical reactions

8.2 Standard enthalpy change of neutralization, solution, formation and

combustion

8.3 Hesss law

F5

9. Rate of reaction ( Book 4A )

9.1 Rate of chemical reaction

9.2 Factor affecting rate of reaction9.3 Molar volume of gases at r.t.p.

F5


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10. Chemical equilibrium ( Book 4A )

10.1 Dynamic equilibrium

10.2 Equilibrium constant

10.3 The effect of changes in concentration and temperature on chemical

equilibria

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11. Chemistry of carbon compounds ( Book 4B )

11.1 Introduction to selected homologous series

11.2 Isomerism

11.3 Typical reaction of various functional groups

11.4 Inter-conversion of carbon compounds

11.5 Importance of organic substances

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12. Patterns in the Chemical World ( Book 4B )

12.1 Periodic variation in physical properties of the elements Li to Ar

12.2 Bonding, stoichiometric composition and acid-base properties of the

oxides of elements Na to Cl

12.3 General properties of transition metals

F5

B. Elective Part

Topic Content

13 Industrial chemistry ( Book 5 )

13.1 Importance of industrial processes

13.2 Rate equation

13.3 Activation energy

13.4 Catalysis and industrial processes

13.5 Industrial processes

13.6 Green Chemistry

F6

14 Material chemistry ------

15 Analytical chemistry ( Book 7 )

15.1 Detecting the presence of chemical species

15.2 Separation and purification methods

15.3 Quantitative methods if analysis

15.4 Instrumental analytical methods

15.5 Contribution of analytical chemistry to our society

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Part 2. Revision

Pleasestudy wellthe following fundamental knowledge of Chemistry.

You will have a quiz in early September. The quiz will cover chapters 1, 5 to 8.

Chapter 1 Fundamentals of Chemistry

What is chemistry?

The study of substances, about their

- compositions,- structures,- properties ( physical and chemical ) and- the changes among them.

Chemistry is closely related to our daily life, for examples :

- Clothing, Food , Housing , Transport , Medicines , etc.

Classifications of matter:

Element:- a pure substance that cannot be broken down into anything simpler by chemical methods

- a pure substance that is made up of one kind of atoms only

Compound: a pure substance made up of two or more elements chemically combined together

Mixture : consists of two or more pure substances ( elements or compounds ) which haveNOT chemically combined together.


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Observations in experiments include FOUR activities :- Seeing with eyes , i.e. What color change , gas bubbles produce , solid dissolve,

precipitate form / what color flame/ ...

- Feeling with hands, i.e. solution become hot / warm / cold /

- Smelling with nose , i.e. with burning smell , choking / pungent smell,

- Hearing with ears , i.e. hissing sound produce , burn with pop sound,

Physical change : occur without changing into new substances ,usually just involves states change ( solid , liquid , gas )

Chemical change: occur chemical reactions involved, i.e. new substances are formed

Physical and chemical properties of substances

Physical properties of substances are those properties that can be determined without thesubstance changing into another into substance.

ExamplesPhysical

Property Chalk Iron clip Table salt Water

appearance white solid Shiny silver solid White solid

odour --- --- No smell

taste --- --- Salty

hardness hard but brittle hard Hard

Density* Low high ----

Solubility ( in

water )

Insoluble Insoluble Soluble

Malleability &

ductility

non malleable

& non-ductile/

hard but brittle

Malleable &

ductile

non malleable

& non-ductile

Electrical

conductivity

Non-conductor

/ insulator

Good conductor Non- ( solid state)

Cond- ( molten )

Thermal

conductivity

Poor thermal

conductor

Good thermal

conductor

Poor thermal

conductor

Melting points

and boiling point

Low high high


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Chemical properties :- of the substances are chemical reactions take place at the respective conditions.

e.g. rusting of iron

Iron only rusts if presence of water and oxygen.

e.g. burning of a candle

Candle can be burned if there are oxygen and with sufficient of energy supply to start

the reaction.

Hazard warning labels: ( Laboratory Handbook P.3 )Label Hazard Example Safety Precautions

Explosive -Potassium, Sodium,

explosive,

Keep away from heat and flame

Flammable Hydrogen , LPG,

town gas, alcohol,

- Keep away from heat and

flame

- stored in wellventilated place

Toxic Chlorine, carbon

monoxide, hydrogen

sulphide ,

-Handle it in the fume cupboard.

-Wear gloves

Carcinogenic Benzene ,

Tetrachloromethane,

Asbestos

-Handle it in the fume cupboard.

-Wear gloves

Oxidizing Concentrated nitric

acid , potassium

permanganate,

- wear gloves and safety glasses

Corrosive conc. acids ,

conc. alkalis,


Harmful Lead compounds,

Trichloromethane,


Irritant Dilute acids and

alkalis,



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Chapter 5 Atomic structure

Classifications of Elements(i) By Physical states

- Solid ( 104 )

- Liquid ( 2 , Br and Hg )

- Gas ( 12 , H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn, Uuo)

(ii)

Metal and Non-metal

Properties of metals and non-metals:Properties Metals Non-metals

State

at room temp &

pressure ( r.t.p.)

All are solids

except Hg(l)

Most are gases (O2, N2, He, etc.),

Some are solids (C, S, etc),

one liquid (Br2)

Melting pt & boiling pt usually High Low, (except C, Si)

Appearance Shiny, silvery white;

(except Au and Cu ,

golden /shiny brown )

Dull ( except graphite ) and in

various colours

Hardness and strength usually Hard and strong Not uniform

Malleability & ductility Malleable & ductile Brittle

Density High Low

Thermal conductivity

and electrical

conductivity

All are good

conductors

Bad conductors of heat,

non-conductors of electricity,

(except graphite)


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Semi-metals (metalloids): boron and silicon (Si is a semi-conductor which is used in makingcomputers chip )

Subatomic particlesSymbol Relative mass Relative charge Position in atom

Proton p 1 + 1 Inside the nucleus

Neutron n 1 0 Inside the nucleus

Electron e- 0 - 1 Moving around nucleus

Full symbol of an atom: XAZ A: mass number = no. of p + no. of n (different for isotopes)

Z: atomic number = no. of p (fixed for each element)

Isotopes:Isotopes are atoms of the same element with the same number of protons ( atomic number )

but different number of neutrons ( mass number ).

Relative atomic mass ( R.A.M. ) :- is the averaged mass of isotopes of the element.

e.g. chlorine-35 & chlorine-37 have relative abundances 75% & 25% respectively,

the R.A.M. of chlorine = 35 x 75% + 37 x 25% = 35.5

( No unit ! One decimal place !)


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Patterns in the Periodic Table: Across a period, elements change from metals through semi-metals to non-metals

(i.e. more non-metallic)

An interesting rule: an element with group no. > period no. is a non-metal (except H andnoble gases)

Groups : similarities and trends down a group* Elements in the same group have similar chemical properties.

* Reactivity increases / decreases down the group.

Properties ofGroup I elements (alkali metals: Li, Na, K, Rb, Cs, Fr ):-- soft (can be cut by knife)

-- low density (float on water)

-- reactive (more reactive than other groups, stored under paraffin oil), e.g. all react with

water to form hydroxide solution and give off hydrogen; Observation of reaction of alkali

metals with water (p.144)

Reactivity of metals increases down the group

(reactivity: Li < Na < K < Rb < Cs < Fr)


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Properties ofGroup VII elements (halogens, X : F, Cl, Br, I, At ):-- poisonous

-- with pungent choking smell

-- form diatomic molecules, X2

-- m.p. & b.p. increases down the group: F2 : (g), Cl2 : (g), Br2 : (l), I2 : (s);

because van der Waals forces increase with the size of molecules

-- colour intensity increases down the group,

F2(g) : pale yellow

Cl2(g) : greenish yellow

Br2(l) : dark red / reddish brown Br2(aq) : orange / reddish brown, Br2(g): brown

I2(s) : dark purple /black I2(aq) : brown I2(g) : purple

I2(heptane) : purple

-- reactive :

Reactivity of non-metals decreases down the group

( reactivity : F > Cl > Br > I )

Properties ofGroup 0 elements (noble gases: He, Ne, Ar, Kr, Xe, Rn)-- colourless gases

-- density down the gp (He is less dense than air, but Xe is much denser than air)

-- exist as monoatomic molecules

-- m.p. & b.p. down the gp because van der Waals forces increase with molecular size

-- unreactive

(Qhaving stable electronic arrangement, He is duplet, the others are octet)


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Chapter 7 & 8 Chemical bonding : Ionic bonding (Ch.7) and Covalent bonding (Ch.8)

All ionic compounds can conduct electricity when they are in molten or in aqueoussolution

because ofmobile ions produced in molten state or in aqueous solution. (In solid state, theions are not mobile, but in molten or aqueous states, the ions become mobile!)

Ions:Cation: when atom loses e

-

, it becomes a cation and carries +ve charge, (usually metals

form cations)

Anion : when atom gains e-, it becomes an anion and carries ve charge, (usually

non-metals form anions)

Simple ion : a ion derived from a single atom.

Polyatomic ions : a ion derived from a group of atoms.

Examples :

Cl

chloride ion is a simple anion.

Na+

sodium ion is a simple cation.

SO42-

sulphate ion is a polyatomic anion.

NH4+

ammonium ion is a polyatomic cation.

Exercises :

OH

hydroxide ion is a .

Fe3+

is a

Br is a


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Names & formulae of ions: (names & formulae of ionic compounds)Cations Anions

Charge Formula Name Charge Formula Name

1+ Na+

K+

Cu+

Ag+

NH4+

H+

sodium

potassium

copper (I)

silver

ammonium

hydrogen

1- H

F-

Cl-

Br-

I-

OH-

NO3-

NO2-

HCO3-

HSO4-

MnO4-

ClO-

hydride

fluoride

chloride

bromide

iodide

hydroxide

nitrate

nitrite

hydrogencarbonate

hydrogensulphate

permanganate

hypochlorite

2+ Mg2+

Ca2+

Fe2+

Cu2+

Ni2+

Mn2+

Pb2+

Hg2+

Zn2+

magnesium

calcium

iron(II)

copper(II)

nickel(II)

manganese(II)

lead(II)

mercury(II)

zinc

2- O2-

S2-

SO42-

SO32-

CO32-

CrO42-

Cr2O72-

oxide

sulphide

sulphate

sulphite

carbonate

chromate

dichromate

3+ Al3+

Fe3+

Cr3+

aluminium

iron(III)chromium(III)

3- N3-

P3-

PO43-

nitride

phosphidephosphate


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Colours of ions:Fe

2+Fe

3+Cu

2+Ni

2+Cr

3+Cr2O7

2- Mn

2+ MnO4

-

pale green brown Blue/green green green orange Colourless purple

/ Very pale pink

Migration of ions: - Evidence of presence of ions ( in Book 1B, P.144-146 )

Under electric field / during electrolysis, the migration of coloured ions can be observed. For KMnO4, purple colour ( MnO4- ) is observed at the +ve electrode. ( Figure 7.5 ) For CuCr2O7, blue colour ( Cu2+ ) is observed at the ve electrode while orange colour

(Cr2O72-

) is observed at the +ve electrode. ( Figure 7.4 )

Expt.7.2 Migration of potassium and permanganate ions: Observation:

purple colour moves towards the +ve electrode Conclusion:

KMnO4 consists of colourless K+ ions and purple MnO4- ions. In aqueousKMnO4(aq), the ions become mobile. So, the negative, purple MnO4

-ions move

towards the +ve electrode while the positive, colourless K+

ions move towards

the ve electrode (which cannot be seen).

Note: the filter paper should be moistened with sodium sulphate solution to increaseelectrical conductivity (Qit provides more ions to conduct electricity)


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Summary and comparison of ionic and covalent bondings.

Ionic bonding Covalent bonding

Formed between metals & non-metals to

attain noble gas electronic arrangement

Formed between non-metals to

attain noble gas electronic arrangement

By e-transfer,

metal atoms lose e-to form cations (+);

non-metal atoms gain e-to form anions (-)

By e-sharing,

non-metal atoms share e-between nuclei to

form molecules, e.g. Cl2 , CH4, etc.

Strong non-directional electrostatic attraction

between +ve and ve ions.

Strong directional electrostatic attraction

between the shared electrons and the two

nuclei of the bonded atoms.

Electron diagram of MgF2

Ionic formula : ( F-

)(Mg2+

)( F-

) /(Mg

2+)( F

-)2

Empirical formula : MgF2

Electron diagram of NCl3

Structural formula:

Molecular formula : NCl3

* names & formulae names & formulae

of ions of ionic cpds

e.g. magnesium ion and fluoride ion

magnesium fluoride

with water of crystallization as:

n water

e.g. CuSO47H2O

copper (II) sulphate -7-water

* all ionic compounds are in giant ionic

structure, i.e. each Mg2+

ion is surrounded

by 6 F-ions and vice versa.

* molecular formula & structural formula

* single bond (), double bond (=),

triple bond ()

* bond pair electrons & lone pair electrons

* shapes of molecules: linear (CO2),

V-shaped (H2O), trigonal pyramidal

(NH3), tetrahedral (CH4)

* atomicity of molecules ( for elements )

monoatomic (He), diatomic (Cl2),

triatomic (O3)


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Ionic compound

An ionic compound ( or ionic substance ) is a compound which consists ions.

Covalent substance

A covalent substance is a non-ionic substance in which the atoms are held together by covalent

bonds.

Molecule

A molecule is the smallest part of an element or a compound which can exist on its own under

ordinary conditions.

Distinguish between name, symbol & formula of some elements:

Element Atomic / Chemical symbol Molecular formulaHydrogen H H2

Nitrogen N N2

Oxygen O O2

Chlorine Cl Cl2 ( for all halogens )

Helium He He ( for all noble gases )

Sodium Na ---

Sulphur S S8


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Part 3. Exercises

1. a) Complete the following table of particles and their particle composition. The particles

are either atoms or ions.

Number of

Particle Mass number Protons Neutrons Electrons

O

O 2

Cl

W 37 20 17

Y 37 17 18

Z 10 10

Ni

Ni2+

Ca

b) What is the relationship between 35Cl and particle W? Explain your answer.

c) What is the name of

(i) W ? (ii) Y ?

(iii) Z ?

d) Which of the above particles are metals ?e) Which of the above particles are ions ?

18

17

35

64

64

39


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2. The table below shows the colours of solutions of three ionic compounds containing four ions:

W+, X

2+, Y

2and Z

2.

Ionic compound Colour of solution of compound

W2Z Colourless

W2Y Orange

XZ Blue

Deduce and explain the colour of the ions :

W+(aq), X

2+(aq), Y

2(aq), Z

2(aq).

3. Iron occurs naturally as a mixture of four isotopes. The relative abundance of these isotopes is

tabulated below:

Isotope54

Fe56

Fe57

Fe58

Fe

Abundance (%) 5.84 91.68 2.17 0.31

a) What is meant by the term 'isotopes'?

b) Calculate the relative atomic mass of iron.


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4. An element X occurs naturally as a mixture of two isotopes. The relative atomic masses of

the two isotopes are 63.0 and 65.0. The relative atomic mass of X is 63.6. What is the

percentage abundance of the two isotopes?

5. The student places a drop of copper(II) chloride solution at A and a drop of potassium

permanganate solution at B.

microscopicslide

filter papermoistened withsodium sulphatesolution

20 V d.c. power supply+

A B

a) Why is the filter paper moistened with sodium sulphate solution?

b) Write the chemical formula of the ions responsible for the purple colour of potassium

permanganate.

c) What will be observed on the filter paper after an electric current is passed for about 10

minutes? Explain your answer.


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6. The table below gives the group number of four elements.

Element Symbol Group number

Caesium Cs I

Indium In III

Tellurium Te VI

Astatine At VII

a) Would you expect caesium to be a conductor of electricity? Explain your answer.

b) Give the chemical formula of caesium sulphate.

c) Give the chemical formula of indium oxide.

d) Give the chemical formula of tellurium oxide.

e) Caesium and astatine combine to form a compound.

(i) Draw the electron diagram of the compound. (showing the outermost shell electrons only.)

(ii) Would an aqueous solution of the compound conduct electricity? Explain your answer.

f) Astatine and hydrogen combine to form a compound.(i) Draw the electron diagram of the compound (showing the outermost shell electrons only.)

(ii) Give the chemical formula of the compound.


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7. W, X, Y and Z are four different elements. Their atomic numbers and electronic arrangements

of their atoms are as follows.

Element Atomic number Electronic arrangement of atom

W 14 (i)

X 18 (ii)

Y 35 p, q, 18, r

Z 37 p, q, 18, 8, s

a) Calculate the values of p, q, r and s in the above table.

b) In which groups and periods of the periodic table should Y and Z be placed?

c) (i) What is the electronic arrangement of atom

W : X :

(ii) In what way are the electronic arrangements of the atoms of W and X.

(1) similar to one another?

(2) different from one another?

d) Which TWO of the four elements would form

i) an ionic compound?

ii) a covalent compound?


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8. With reference to the part of the periodic table shown below, answer the following questions.

Group

I II III IV V VI VII 0

Period 2 Li Be B C N O F Ne

Period 3 Na Mg Al Si P S Cl Ar

Period 4 K Ca Cr Br

a) Name two elements which are mainly obtained from sea water.

b) Name two elements which are present in the free state ( elemental form ) on land.

c) Explain why argon is monoatomic.

d) Name a metal which can form a coloured anion. Give the chemical formula and colour of

this anion.

e) In what way are the electronic arrangements of the atoms of magnesium and calcium.

i) similar to each other?

ii) different to each other?

f) Point out the gradual change in the reactivity of Group I elements down the group.

g) Suggest TWO gradual changes in the physical properties of the Group VII elements down

the group.


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For Q.9, write your answer in full sentences and in paragraphs

9. "When atoms combine, they tend to achieve the electronic arrangements of atoms of noblegases."

Write an essay to discuss, with reference to suitable examples, how atoms of Group VI elementsachieve the electronic arrangements of atoms of noble gases.

*** The End***

Documents

Chemistry - F3 to F4 Summer Assignments