kimia
TRANSCRIPT
CHAPTER 2:THE STRUCTURE OF THE ATOM
2.1 MATTER: (refer text book pg 11)
1. Particle Theory of Matter : Matter is made up of …………………… and ………………..
particles.
2. The tiny particles may be atoms, ……………….. and ……………………….
3. Kinetic Theory of matter : Matter consists of small particles that always collide among each
other. The particles move faster when energy is ……………… and slower when they are
………….
4. Change of states of matter based on Kinetic Theory:
State of matter Solid Liquid Gas
Draw the particles
arrangement
Particles
arrangement
The particles are
…………….together
in an …………….
manner
The particles are
………… but not in
………….
The particles are
…………….. apart from
each other.
Particles movement Particles can only
…………..and ……..
About their fix
positions
Particles can ………,
………… and ……….
throughout the liquid
Particles can ………….,
……………… and
……… freely
Attractive forces
between the
particles
Very …………………,
…………….. between
particles
Strong ………………
between particles but
then the forces in
solid.
…………………. Forces
between particles
Kinetic energy of
particles …………………….. ………………………. ………………………
1
1
5. When heat energy is supplied to particles in matter, its kinetic energy (increased/decreased)
and the particles in matter vibrate ( faster/ slower) When matter loses heat energy, the
kinetic energy of the particles (increased/decreased) and they vibrate ( faster/ slower).
6. ( A ) ( B )
(
C ) ( D )
A …………………… B ……………………… C…………………… D…………………….
7. The temperature at which a ………………………………. Completely changes to
become a liquid is called ………………………………..
8. Explanation on the heating process of matter (refer text book 15)
point States of matter explanation
A to B
B to C
C to D
2
2
SOLID LIQUID GAS
A
B
C
DTemperature OC
Times/s
9. Explanation on the cooling process of matter
Point State of matter Explanation
P to Q
Q to R
R to S
Freezing point : The temperature at which a …………………… changes into …………….
During the freezing process, the temperature remains unchanged because the heat lost to the
environment is ………….. by the heat released when the liquid particles rearrange themselves
to become solid.
3
3
Temperature OC
Times/s
AB C
D
2.2 THE ATOMIC STRUCTURE
The Historical Development Of Atomic ModelsComplete all the blanks and draw the structure of each atomic model.
Model Structure Characteristic
Dalton’s atomic model(proposed by ………………in…………)
The atom was imagined as a small indivisible ball similar to a very tiny ball.
Thomson’s atomic model(proposed by ……………… in………..)
J.J Thomson discovered the………., a negatively-charged particle.The atom was describe as a sphere of positive charge embedded with electrons.
Rutherford’s atomic model(proposed by ………………… in ……….)
Ernest Rutherford discovered ………, a positively-charged particle in an atom.The central region of atom has a very small positively-charged ……………, which contains almost all the mass of the atom.
Bohr’s atomic model(proposed by ……………… in ………..)
The electrons in an atom move in ………… around the nucleus which contains protons.
Chadwick’s atomic model(proposed by …………..……. in ……….)
Chadwick proved the existence of ……………., the neutral particle in the nucleus.The nucleus of the atom contains protons & neutrons, and the nucleus is surrounded by electrons.…………… contribute approximately to half the mass of an atom.
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4
Subatomic Particle Of An Atom
Fill all the blanks and complete the table. (refer text book pg 18)
1. Atoms are made up of subatomic particles namely …………….., …………… and …………..
………….. and …………….. are found in the nucleus of an atom while electrons surround the nucleus.
Subatomic particle Symbol Relative mass Relative electric charge
ProtonNeutron
Electron
2. The proton number of an element is the number of ………………… in its atom.
PROTON NUMBER, Z = NUMBER OF. PROTON
3. Protons and neutrons are collectively called nucleons. The nucleon number of an element is the total number of ……………… and …………….. in its atom.
NUCLEON NUMBER, A = NUMBER OF. PROTON + NUMBER OF NEUTRON
4. The nucleon number is also known as the mass number.
NUMBER OF NEUTRON = NUCLEON NUMBER -- PROTON NUMBER = A -- Z
5. Symbols Of ElementsThe standard representation for an atom of any element shows the proton number and the nucleon number of the element. It can be written as follows:
A XZ
# A – Nucleon number Z – proton number X – symbol of element
5
5
1H1
21Sc45
Proton number Nucleon number
2He4
3Li7
4Be9
5B11
6C12
7N14
8O16
9F19
10Ne20
11Na23
12Mg24
13Al27
14Si28
15P31
16S32
17Cl35
18Ar40
19K39
20Ca40
21Sc45
Consider part of the periodic table of the element above and complete the table below.
Element Symbol Proton number
No. of electron
Nucleon number
No. of neutron
Standard representation
Scandium
Aluminium
Argon
Beryllium
Boron
Calcium
Carbon
Chlorine
Fluorine
Helium
Hydrogen
Lithium
Magnesium
Neon
Nitrogen
Oxygen
Phosphorus
Potassium
2.3 ISOTOPES AND THEIR IMPORTANCE
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6
2.1 Isotopes And Their Importance ( refer text book pg 20)
** Isotopes are atoms of the same element with different numbers of neutrons.
Complete the table:
Element Number of isotopes
Symbol of isotopes
Number of protons
Number of electrons
Number of neutrons
Name of isotopes
Hydrogen 31
1 Hydrogen-2
1
Oxygen 38 8 Oxygen-16
8 9
Carbon 36 Carbon-126 7
6 8
Chlorine 2 17
17 20Bromine 2 35 Bromine-80
35 35 Bromine-81
* Uses of isotopes in Our Daily Lives (refer text book pg 21)
1. Cobalt-60 : _____________________________________________________. 2. Gamma rays of Cobalt-60 : ________________________________________
3. Carbon-14 : ______________________________________________________ 4. Phosphorus-32 : __________________________________________________
2.4 THE ELECTRONIC STRUCTURE OF AN ATOM
1. The elektron are filled in specific shells. Every shell can be filled only with a certain number of electrons. For the elements with proton number 1-20:-
First shell can filled with a maximum of ……………. electronsSecond shell can filled with a maximum of ……………. electronsThird shell can be filled with a maximum of …………….electrons
7
7
Third shell filled with 8 electrons
Second shell filled with 8 electrons
First shell with 2 electrons
Lithium Atom
Sodium Atom
2. Valance electron : Electron in the …………………. shell of a neutral atom.
CHAPTER 3: CHEMICAL FORMULAE AND EQUATIONS
3.1 RELATIVE ATOMIC MASS (RAM) AND RELATIVE MOLECULAR MASS (RMM)
Relative atomic mass of an elemant , Ar
= The average mass of an atom of the element 1/12 x the mass of an atom of carbon-12
Example: Ar of C=12Ar of O=16Ar of Mg=24
Relative molecular mass of a substance, Mr
= The Average mass of a molecule of the substance 1/12 x the mass of an atom of carbon-12
Number of proton
Number of electron
Number of neutrons
Proton number
Nucleon number
Electron arrangement
Number of proton
Number of electron
Number of neutrons
Proton number
Nucleon number
Electron arrangement
8
8
x
x
x
1
Li 3
23
Na 11
x
x
x
x x
x
x
xx
x
xx
Calculating Relative molecular mass,Mr
Mr= The sum of Ar of all atoms present in one molecule
Example:
Mr of Water, H2O = 2(1) + 16 = 18
Mr of Carbon dioxide, CO2 = 12 + 2(16) = 44
For ionic substance , Relative formula mass , Fr = The sum of Ar of all atoms present in the formula
Example:
Fr of Magnesium oxide, MgO = 24 + 16 = 40Fr of Sodium chloride, NaCl = 23 + 35.5 = 58.5
1. Calculate the Relative molecular masses of the substances in the table below.
Substance Molecular formula Relative molecular mass, Mr
Hydrogen gas H2 2(1) = 2
Propane C3H8
Ethanol C2H5OH
Bromine gas Br2
Methane CH4
Glucose C6H12O6
Ammonia NH3
[Relative atomic mass : H,1; C,12; O,16; Br,80 ; N,14 ]
2. Calculate the relative formula masses of the following ionic compounds in the table.
9
9
2 Hydrogen atomsMolecular
formula
Relative atomic mass for OxygenRelative atomic mass
for Hydrogen
All Ar, Mr and Fr have no unit
Substance Compound formula Relative formula mass, Fr
Potassium oxide K2O 2(39) + 16 = 94
Aluminium sulphate Al2(SO4)3 2(27)+3[32+4(16)]=342
Zinc nitrate Zn(NO3)2
Aluminium nitrate Al(NO3)3
Calcium carbonate CaCO3
Calcium hydroxide Ca(OH)2
Hydrated copper(II) sulphate
CuSO4.5H2O 64 + 32 + 4(16) + 5[2(1) + 16]=250
Hydrated sodium carbonate
Na2CO3.10H2O
[Relative atomic mass: O,16; C,12; H,1; K,39 ; Cu,64 ; Zn, 65; Cl, 35.5 ; Al, 27 S,32 ; Ca, 40; Na,23; N, 14]
3.2 The Mole and the number of particles
1. To describe the amount of atoms, ions or molecules , mole is used2. A mole is an amount of substance which contains a constant number of particles
(atoms, ions, molecules which is 6.02 x 1023
3. The number 6.02 x 1023 is called ………………………….. (NA)4. relationship between number of moles and number of particles (atom/ion/molecules):
x Avogadro Constant ∻ A
vogadro Constant
Number of moles Number of particles
………….. mol of carbon atoms 3.01 x 1023 atoms of carbon
10
10
number of moles
number of nmolecules
0.2 moles of hydrogen gas (i) …………….. molecules of hydrogen
(ii) ……………. Atoms of hydrogen
………………… mol of carbon dioxide molecules
x 10 23 molecules of carbon dioxide contains :
…………atoms of C and ……. Atoms of O
3.3 Number of Moles and Mass of Substances
1. Molar Mass : (a) Molar Mass is the mass of one mole of any substance.(b) Molar Mass is the relative atomic mass, relative molecular mass and relative
formula mass of a substance in g mol -1
(c) Molar Mass of any substance is numerically equal to its relative mass.
X RAM/RMM/RFM
∻ RAM/RMM/RFM
2. Complete the following table.
Element/compoundChemical formule RAM/RMM/RFM Calculate
Copper Cu RAM= 64 (a)Mass of 1 moll
(b) Mass of 2 mol :
(c)Mass of ½ mol:
(d)Mass of 3.01x1023 Cu atoms:
11
11
NumberOf
moles
Mass in g
Sodium hydroxide NaOH RFM= 40 (a) Mass of 3 mol of sodium hydroxide
(b) Number of moles of sodium hydroxide in 20 g
Zinc nitrate Zn(NO3)2 RFM = a) Number of moles in 37.8 g of zinc nitrate:
3.4 Number of Moles and Volume of gas
1. Molar volume of a gas : Volume occupied by one mole of any gas.
2. The molar volume of any gas is 24 dm3 at room conditions and 22.4 dm3 at standard temperature and pressure (STP)
3. generalization : One mole of any gas always occupies the same volume under the same temperature and pressure;
Example i) 1 mol of oxygen gas, 1 mol of ammonia gas, 1 mol helium gas and 1 mol sulphur dioxide gas occupies the same volume of 24 dm3 at room condition
x 22.4/24 dm3
∻22.4/24 dm3
12
12
Number of moles of gas
Volume of gas
Volume of gas (dm3)
Number of moles Mass in gram No of particles
Complete the above diagram (Refer to Page 33,34 & 38-Chemistry textbook)
The Molecules and the Volume of Gas
1. What is the volume of 0.3 mole of sulphur dioxide gas at STP?[Molar volume: 22.4 dm3 mol-1 at STP]
(Ans: 6.72 dm3)
2. Find the number of moles of oxygen gas contained in a sample of 120 cm3 of the gas at room conditions.[Molar volume: 24 dm3 mol-1 at room conditions]
(ans: 0.005 mol)3. Calculate the number of water molecules in 90 g of water.
[Relative atomic mass: H, 1; O, 16. Avogadro constant, NA: 6.02 x 1023 mol-1]
(Ans; 3.01x 1024 molecules)4. What is the volume of 24 g methane at STP?
[Relative atomic mass: H, 1; C, 12. Molar volume: 22.4 dm3 mol-1 at STP]
(Ans: 33.6 dm3)5. How many aluminium ions are there in 20.4 g of aluminium oxide?
[Relative atomic mass: O, 16; Al, 27. Avogadro constant, NA: 6.02 x 1023 mol-1]
(2 x 0.2 x 6.02 x1023)6. Calculate the number of hydrogen molecules contained in 6 dm3 of hydrogen gas at
room conditions.
13
13
Relative Atomic Mass : Fe = 65, Ca = 40, Cl = 35.5, Mg = 24, H = 1, O = 16, C =12Avogadro number = 6 x 1023,
[Molar volume: 24 dm3 mol-1 at room conditions Avogadro constant, NA: 6.02 x 1023 mol-1]
(Ans: 1.505x1023 molecules)7. Find the volume of nitrogen in cm3 at STP that consists of 2.408 x 1023 nitrogen
molecules.[Molar volume: 22.4 dm3 mol-1 at STP. Avogadro constant, NA: 6.02 x 1023 mol-1]
(Ans: 8.96 dm3 )
3.5 CHEMICAL FORMULAE
1. Chemical formulae- A set of chemical symbols for atoms of elements in whole numbers representing chemical substances.
Chemical subtance Chemical formulae Notes
Water
------------
Propene
-------------
NH3
C3H8
2 atoms of H combine with 1 atom of O
----- atoms of H combine with 1 atom of N
3 atoms of C combine with ----- atom of H
1. There are two types of chemical formulae
** Empirical Formula The simplest whole number ratio of atoms of each element in the compound.
14
14
** Molecular Formula The actual number of atoms of each element that are present in a molecule of the compound
Remember:
Example: Compound – Ethene Compound – GlucoseMolecular formula - Molecular formula -
Empirical formula - Empirical formula -
2. To find the empirical formula of a compound Example of calculation: a) When 11.95 g of metal X oxide is reduced by hydrogen, 10.35 g of metal X is produced. Find the empirical formula of metal X oxide [ RAM; X,207; O,16 ]
Element X O
Mass of element(g) 10.35 11.95-10.35
Number of moles of atoms 10.35÷207 (11.95-10.35)÷16
Ratio of moles
Simplest ratio of moles
Empirical formula : ……………
b) A certain compound contains the following composition: Na 15.23%, Br 52.98% , O 31.79%, [ RAM : O, 16; Na, 23; Br,80] (Assume that 100g of substance is used)
Element Na Br O
Mass of element(g) 15.23 52.98 31.79
Number of moles of atoms 15.23 ÷23 52.98÷80 31.79÷16
Ratio of moles
Simplest ratio of moles
Empirical formula:
Compound Molecular Formula Empirical formula Value of n
Water H2O
Carbon Dioxide CO2 CO2
15
15
Molecular formula = (Empirical formula)n
Sulphuric Acid H2SO4
Ethane C2H4 CH2
Benzene C6H6
Glucose C6H12O6
a) 2.58g of a hydrocarbon contains 2.16 g of carbon. The relative molecular mass of the hydrocarbon is 86. [RAM H,1; C,12]
i. Find the empirical formula of the hydrocarbon
ii. Find the molecular formula of the carbon.
3. Chemical Formula for ionic compounds:*Memorise… The formulae of some common cations and anions :
Cation Formula Anion Formula
Hydrogen ion Flouride ion
Lithium ion Chloride ion
Sodium ion Bromide ion
Potassium ion Iodide ion
Magnesium ion Hydroxide ion
Calcium ion Nitrate ion
Barium ion Manganate(VII) ion
Copper(II) ion Ethanoate ion
Iron(II) ion Oxide ion
Iron (III) ion Sulphate ion
16
16
Lead (II) ion Sulphide ion
Zinc ion Carbonate ion
Chromium (III) ion Dichromate (VI) ion
Aluminium ion Phosphate ion
Ammonium ion
Silver ion
17
17
a) Chemical formula of an ionic compound comprising of the ions Xm+ and Yn- is constructed by exchanging the charges of each element. The formula obtained will XnYm
example : Sodium oxide Copper (II) nitrate Na+ O2- Cu2+ NO3
- +1 -2 2+ -1
2 1 1 2 = Na2O = Cu(NO3)2
Construct a chemical formula for each of the following ionic compounds:
(a). Magnesium chloride (b). Potassium carbonate (c). Calcium sulphate
(d). Copper (II) oxide (e). Silver nitrate (f). Zinc nitrate
(g). Aluminium oxide (h). Iron(II) hydroxide (i). Lead(II) sulphide
3.6 CHEMICAL EQUATIONS
Example: C (s) + (g) (g)
Reactant product
*Qualitative aspect of chemical equation:
1. Arrow in the equation the way the reaction is occurring2. Substances on the left-hand side reactants.3. Substances on the reight-hand side products.4. State of each substance solid : (s), liquid (l), gas (g) and aqueous reaction
(aq)
Example: 2 (g) + (g) 2 (l)
2 molecules 1 molecule 2 molecules Or or or2 mol 1 mol 2 mol
* Quantitative aspect of chemical equations
1. Coefficients in a balanced equation the exact proportions of reactants and products in a equation.
Write a balanced equation for each of the following reactions and interpret the equations quantitatively.
(a). Carbon monoxide gas + oxygen gas carbon dioxide gas ______________________________________________________________________Interpreting: ___________________________________________________________________
(b). Hydrogen gas + nitrogen gas ammonia gas ______________________________________________________________________Interpreting: ___________________________________________________________________
(c). Aluminium + Iron (III) oxide aluminium oxide + Iron ______________________________________________________________________Interpreting: ___________________________________________________________________
** Numerical Problems Involving Chemical Equations
Hydrogen peroxide decomposes accordin to the following equation:2 (l) 2 (l) + (g)
1. Calculate the volume of oxygen gas, measured at STP that can be obtained from
the decomposition of 34 g of hydrogen peroxide, .
[Relative atomic mass : H, 1 ; O, 16. Molar volume : 22.4 at STP]
(Ans: 11.2 dm3)
2.Silver carbonate Ag2CO3 breaks down easily when heated to produce silver metal2 Ag2CO3(l) 4 (s) + 2 (g) +
Find the mass of silver carbonate that is required to produce 10 g of silver
[Relative atomic mass: C, 12 ; O, 16 ; Ag, 108]
(Ans : 12.77g)
3. 16 g of copper (II) oxide, is reacted with excess methane, . Using the equation below, find the mass of copper that is produced.[Relative atomic mass : Cu, 64 ; O, 16]
4 (s) + (g) 4 (s) + (g) + 2 (l)
(Ans : 16 g)
4.A student heats 20 g of calcium carbonate strongly. It decomposes according to the equation below:
(s) (s) + (g).(a). If the carbon dioxide produced is collected at room conditions, what is its volume?(b). Calculate the mass of calcium oxide, produced.[Relative atomic mass: C, 12 ; O, 16; Ca, 40. Molar volume : 24 dm3 at room conditions]
(Ans : (a). 4.8 dm 3 (b) 11.2 g)
CHAPTER 4 : PERIODIC TABLE of ELEMENTS
4.1 THE PERIODIC TABLE OF ELEMENTSHistorical Development of the Periodic Table
Arrangement of elements in the Periodic Tablea) Elements are arranged in an increasing order of proton numberb) Vertical columns are called group ( Group 1 18)c) Horizontal rows are called period ( Period 1 7)d) Elements with similar chemical properties are placed in the same groupe) The group number of the elements with 1 to 2 valence electrons
= the number of valence electrons in its atom.f) The group number of the elements with 3 to 8 valence electrons
= the number of valence electrons in its atom + 10g) The period number of an element = the number of shells occupied with electrons
in its atom.
1. Complete the table below
Element
Electron arrangement
2.1 2.4 2.7
Number of valence electrons
2 8
Group 14 17Number of shells occupied
2
Period 2Element
Electron arrangement
2.8.1
Number of valence electrons
6
Group 1 16 2Number of shells occupiedPeriod 3 4
2.An atom of element E has 10 neutrons. The nucleon number of element E is 19. In which group and period is element E located in the Periodic Table?
3. An atom of element G has 3 shells occupied with electrons. It is placed in group
17 of the Periodic Table. What is the electron arrangement of atom G?
4.2 Group 18 Element known as noble gases: Helium, neon, argon, krypton, xenon & radonmonoatomicall noble gases are inert – chemicallt unreactive
** The electron arrangement of noble gases are very stable because the outermost occupied shells are full
Uses of Group 18 elements:1. Helium gas – to fill airships and weather balloons2. Neon gas – used in advertising lights and television tubes3. Argon gas – to fill light bulbs4. Krypton gas – used in lasers to repair the retina of the eye5. Radon gas – treatment of cancer6. Xenon gas – used for making electron tubes and stroboscopic lamps
4.3 Group 1 Elements (Alkali Metals) Lithium, sodium, potassium, rubidium, caesium & francium uses of Group 1 elements:a) Lithium – batteries in calculator, watches and camerasb) Sodium - in soda-lime glass
c) Potassium - as fertiliser.
* physical properties: softmetals, low densities, low melting & boiling points, silvery and shiny surfaces, good conductors of heat and electricity
*Chemical Properties of Group 1 Elements1. react vigorously with water to produce alkaline metal hyrdroxide solutions and
hydrogen gas
Example: + + Write down the balanced equation when potassium reacts with water_______________________________________________________________
2. react (burn) in oxygen gas rapidly to produce white solid metal oxides
Example: + Write down the balanced equation when rubidium reacts with oxygen_______________________________________________________________
3. burn in chlorine gas , to form white solid metal chlorides.
Example: + Write down the balanced equation when potassium reacts with chlorine gas_______________________________________________________________
** The reactivity of Group 1 elements increases when going down the group. Explain why._______________________________________________________________
______________________________________________________________________________________________________________________________
** Potassium reacts more vigorously with water as compared to sodium. Explain.(Proton number: Na, 11 ; K, 19)____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
(refer text book pg 67&68)
To Investigate The Chemical Properties of Lithium, Sodium & Potassium(A) The Reaction of alkali metals With Water,
Problem Statement: How does the reactivity of Group 1 elements change when they react with water?
Hypothesis: When going down Group 1, alkali metals become more reactive in their reactions with water.
Variables: Manipulated variable – Different types of alkali metalsResponding variable – Reactivity of metalsFixed variables – water, size of metals
Procedure:(refer to practical book pg 39)
Data & Observation (complete this table!)
Alkali metal ObservationLithiumSodiumPotassium
(B) The Reaction of alkali metals With Oxygen, O2 (This procedure also can be used to test the reaction of alkali metals with chlorine gas!)
Problem Statement: _________________________________________________ _________________________________________________
Hypothesis: ______________________________________________________________________________________________________
Variables: Manipulated variable – ________________________________Responding variable – ________________________________Fixed variables – ____________________________________
Procedure;
(refer practical book pg 36)
Data & Observation (This reaction of alkali metals with chlorine gas will give the same observations!)
Alkali metal Observation
LithiumSodiumPotassium
Based on your results, arrange the alkali metals in ascending order of
reactivity._______________________________________________________________Write the chemical equations for the reactions between the products from the combustion of each alkali metal with water.(refer text book pg 67)
1. ____________________________________________________________2. ____________________________________________________________3. ____________________________________________________________
4.4 Group 17 Elements (Halogens) Fluorine, chlorine, bromine, iodine and astatine uses of Group 17 elements:
1) Chlorine – water treatment, bleaching agent2) Bromine – weaker bleaching agent3) Iodine – needed in human thyroid gland to produce hormones
*Physical properties: Low melting and boiling points.Fluorine: pale yellow gasChlorine: greenish-yellow gasBromine: reddish-brown gasIodine: purplish-black gas
*Remembermelting and colour of Density
boiling points halogens increases
increase becomesdarker
When going down the Group 17, the melting and boiling points increase. Explain________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
(refer text book pg 70)** Chemical Properties of Group 17 Elements
1. react with water to form two acidsExample: + +
hydrochloric hypochlorus acid acid
Write a balanced equation when bromine reacts with water.__________________________________________________________________
2. in gaseous state react with hot iron to form a brown solid, iron (III) halides.Example: +
Write a balanced equation when iodine vapour reacts with iron
__________________________________________________________________
3. react with sodium hydroxide solution, , to form sodium halide, sodium halite (I) and water
Example: + + +
Write a balanced equation when chlorine reacts with sodium hydroxide solution__________________________________________________________________
The reactivity of Group 17 elements decreases when going down the group. Explain why.______________________________________________________________________________________________________________________________________________________________________________________________________
Chlorine gas reacts more vigorously with hot iron as compared to bromine gas. Explain (Proton number: Cl, 17 ; Br, 35)________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________(refer text book pg 71)
To investigate the Chemical properties of Group 17 elements.The Reaction of halogens with iron (refer practical book pg 44)
Data and Observation (Complete this form)
Halogens Observation
Chlorine
Bromine
Iodine
Based on your results, arrange the halogens, , , in ascending order of reactivity.__________________________________________________________________
Element E is placed below element D in Group 17 of the Periodic Table.(a). Compare the melting and boiling points of element D with element E. Explain your answer _______________________________________________________________ _______________________________________________________________ _______________________________________________________________
(b). Write an equation for the reaction between element D and hot iron _______________________________________________________________
4.5 Elements In A Period (refer text book pg 73)
Example: Period 3 in the Periodic Table – Properties of Elements
Element Na Mg Al Si P S Cl ArProton number 11 12 13 14 15 16 17 18Electron arrangementAtomic radius (pm)
186 160 143 118 110 104 100 94
Physical state at room temperature
Solid Solid Solid Solid Solid Solid Gas Gas
Electronegativity 0.9 1.2 1.5 1.8 2.1 2.5 3.0 -
* Across Period 3: (refer text book pg 73)
1. The proton number ________________ by one unit from one element to the next
element
2. All the atoms of elements have _______________ shells occupied with electrons.
3. The number of valence electrons in each atom _______________ from 1 to 8.
4. The physical state at room temperature changes from __________ to ___________
5. The atomic radius (atomic size) of elements ________________.
_________________________________________________________
_________________________________________________________
6. The electronegativity of elements. _______________________
_________________________________________________________
_________________________________________________________
7. The oxides of elements change from basic to acidic properties.
Example:, , ,
Below are some oxides of elements of Period 3.
(a). Which of these oxides can react with(i) dilute nitric acid, ?________________________________________
*Sodium oxide, *Silicon (IV) oxide, *Aluminium oxide, *Sulphur dioxide,
(ii) sodium hydroxide, solution?_______________________________
(b). Based on your answers in (a), what inferences can you make about the properties of each of the oxides?_______________________________________________________________
The above show the symbols of lithium, carbon and fluorine.
(a).Which period in the Periodic Table can you find the three elements? Explain._______________________________________________________________
(b).Arrange the three elements in order of increasing atomic size._______________________________________________________________
(c). Compare the electronegativity of the three elements. Explain your answer.______________________________________________________________________________________________________________________________
4.6 Transition Elementselements from Group 3 to Group 12 in the Periodic Table
all are metals
high melting and boiling points ; high densities
good conductors of heat and electricity.
exhibit three special characteristics:
1. transition elements show different oxidation numbers in their compounds.
Example: Iron: 2 oxidation numbers +2, +3
Copper: 2 oxidation numbers
Q2
, ,
2. transition elements form coloured ions or compounds.
Example: 2+ - blueMnO4- - purple
Fe2+ - green CrO42- - yellow
Fe3+ - brown
3. transition elements and their compounds are useful catalysts.
Example: (refer text book 77)
1. Haber process – Manufacture of ___________
Catalyst: iron
2. Ostwald process – manufacture of ______________
Catalyst: __________
3. Manufacture of margarine
Catalyst: _____________
4. Contact process – manufacture of ______________
Catalyst: ___________________
****(Zinc is usually not classified as a transition element because it does not exhibit the
special characteristic of transition elements!)
****(Precious stones such as emerald, rubies, sapphire and jade are beautiful due to the
colours of the transition element compounds present in them!)
1 Diagram 1.1 shows the atomic structure of elements X and Y.(Rajah 1.1 menunjukkan struktur atom bagi unsur X dan Y.)
DIAGRAM 1.1
(a) What is the proton number of element X?(Apakah nombor proton bagi unsur X?)
………………………………………………………….…………………….…………………[1 mark]
(b) (i) Atom of element X has isotopes. What is meant by isotopes?(Atom unsur X mempunyai isotop. Apakah yang dimaksudkan dengan isotop?)
…………………………………………………………………….………………………[1 mark]
(ii) State one example of an isotope. (Nyatakan satu contoh isotop.)
……………………………………………………………………………………………[1 mark]
(c) (i) Atom of element Y has a nucleon number of 23. Calculate the number of neutrons in atom Y.(Atom unsur Y mempunyai nombor nukleon 23. Hitungkan bilangan neutron bagi atom Y.)
……………………………………………………………………………………………[1 mark]
(ii) Write the standard representation of atom Y.(Tuliskan simbol atom unsur Y.)
……………………………………………………………………………………………[1 mark]
(d) Ethanol is an organic compound. Its melting point is –117 oC and its boiling point is 78 oC .(Etanol ialah satu sebatian organik dengan takat lebur – 117 oC dan takat didih 78 oC.)
(i) What is the physical state of ethanol at room temperature?(Apakah keadaan fizik etanol pada suhu bilik?)
……………………………………………………………………………..……………[1 mark]
(ii) Draw the arrangement of particles of ethanol at 100 oC.(Lukiskan susunan zarah etanol pada 100 oC.)
100 oC[1 mark]
(iii) State how the movement of ethanol particles changes when heated from room temperature to 100 oC.(Nyatakan bagaimana pergerakan zarah-zarah etanol berubah apabila dipanaskan dari suhu bilik ke 100 oC.)
…………………………………………….………………………………..…………… [1 mark]
(iv) Sketch the graph of temperature against time when ethanol is heated from room temperature to 100 oC.(Lakarkan graf suhu melawan masa apabila etanol dipanaskan daripada suhu bilik ke 100 oC)
[2 marks]
2 Figure 2.1 shows the chemical symbols which represent elements R, S and T.(Rajah 2.1 menunjukkan simbol kimia yang mewakili unsur-unsur R, S dan T.)
Temperature/oC
Time/min
17 6 19
35 12 39
FIGURE 2.1
(a) (i) Write the electron arrangement of atom T.(Tuliskan susunan elektron bagi atom T.)
………………………………………………………………………………...…[1 mark]
(ii) State the period and the group for element T in the Periodic Table.(Nyatakan kala dan kumpulan bagi unsur T dalam Jadual Berkala.)
Period (Kala) : ….……………………………………………………………..
Group (Kumpulan) ………………………………………………….………...[2 marks]
(b) Atoms of R and S can react to form a compound.(Atom R dan atom S boleh bertindak balas untuk membentuk satu sebatian.)
(i) Name the type of bond in the compound formed between atoms R and S.(Nyatakan jenis ikatan dalam sebatian yang terbentuk antara atom R dan atom S.)
…………………………………………………………………………….[1 mark]
(ii) Give one physical property of the compound in (b)(i).(Beri satu sifat fizik bagi sebatian di (b)(i).)
….……………………………………………………………………………[1 mark]
(c) Atoms of R and T can also react to form a compound. Draw the electron arrangement for the compound formed.(Atom R dan atom T juga boleh bertindak balas untuk membentuk satu sebatian. Lukiskan susunan elektron bagi sebatian yang terbentuk.)
[ 2 marks](d))) Iron, copper, nickel and chromium are examples of transition elements.
(Ferum, kuprum, nikel dan kromium adalah contoh unsur peralihan.)
(i) State the position of transition elements in the Periodic Table.(Nyatakan kedudukan unsur peralihan dalam Jadual Berkala.)
R S T
……………………………………………………………….…….……………[1 mark]
(ii) State two special characteristics of transition elements.(Nyatakan dua ciri istimewa bagi unsur peralihan.)
………………………………………………………………….………………[2 marks]
3 Diagram 2 shows part of the Periodic Table of the Elements.U, V, W, X, Y and Z do not represent the actual symbol of the elements.
DIAGRAM 2
(a) Using the letters in the Periodic Table of the Elements in Diagram 2, answer the following questions.
(i) Choose two elements in period 3
……………………………………………………………………………………………[1 mark]
(ii) Which element will form coloured compound?
……………………………………………………………………………………………[1 mark]
(iii) Write the electron arrangement for an atom of element V.
……………………………………………………………………………………………[1 mark]
(iv) Which element is chemically unreactive ?
……………………………………………………………………………………………[1 mark]
(v) Explain your answer in (a)(iv)
……………………………………………………………………………………………
……………………………………………………………………………………………[2 marks]
UV W
X YZ
(vi) State one of the uses of U.
……………………………………………………………………………………………[1 mark]
(b) When X reacts with cold water, hydroxide solution is formed and a gas is released.
(i) Name the gas
………………………………………….…………………………………………………………[ 1 mark ]
(ii) Write the chemical equation for the reaction
………………………………………………………………………………………[ 2 marks ]