ceramah 2q (2)

7/30/2019 Ceramah 2Q (2)

1/45

Program Peningkatan 2Q

Kimia SPM

Penceramah: Lee Sok Yan

7/30/2019 Ceramah 2Q (2)

2/45

1. Kertas 2

a. Teknik Menjawab

b. Bengkel

(i) Menulis skema pemarkahan

(ii) Menanda kertas

2. Kertas 3

a. a. Teknik Menjawab

b. Bengkel(i) Menulis skema pemarkahan

(ii) Menanda kertas

7/30/2019 Ceramah 2Q (2)

3/45

Technique of Answering

SPM Chemistry Paper 2

1. Underline the command word and note the marks

allocated. 1 point is awarded 1 mark.

2. Underline also important data or information

given so that you do not miss any helpful facts.

3. You are not required to answer in complete

sentences. Answer according to what the

question requires.

7/30/2019 Ceramah 2Q (2)

4/45

Write the name and not the formula of thesubstance.

Q: Name the gas collected at the anode during theelectrolysis of dilute sulphuric acid. [1 mark]

X: O2

Name

A: Oxygen gas

7/30/2019 Ceramah 2Q (2)

5/45

State what can be observed and not the name of theproduct/s.

Q: What is observed when zinc powder is added to

dilute sulphuric acid? [1 mark]

X: Hydrogen gas or H2

State an observation

A: Effervescence occurs/ gas bubbles are

produced

7/30/2019 Ceramah 2Q (2)

6/45

For colour change, state the initial and final colour.

Q: What is observed when chlorine water is added

to iron(II) sulphate solution until there is no further

change? [1 mark]

X: Solution turns brown.

State an observation

A: Pale green solution turns brown

7/30/2019 Ceramah 2Q (2)

7/45

Describe how a test for an ion or a gas is carried out bystating (i) the method and (ii) the expected observation.

Q: State how you would verify that the gas released at the

cathode is hydrogen. [1 mark]

X: Test with a lighted splinter.

Describe a test

A: Place a lighted splinter at the mouth of thetest tube. A pop sound is heard.

7/30/2019 Ceramah 2Q (2)

8/45

Explain

Give reasons for a statement/ fact/ principle.

Q: Blue litmus paper in a solution of hydrogen chloride in

methylbenzene remains unchanged. Explain the

observation. [2 marks]

X: The solution does not show acidic properties.

X: Hydrogen chloride cannot dissolve in methylbenzene.

A: Hydrogen chloride molecules cannot ionise inmethylbenzene.// The solution consists of molecules

only.

No hydrogen ions present.

7/30/2019 Ceramah 2Q (2)

9/45

State the meaning/ Give definition

Definition must be accurate.

Q: State the meaning of a hydrocarbon.

X: An organic compound which has carbon and hydrogen.

A: An organic compound which has only carbon and

hydrogen.

7/30/2019 Ceramah 2Q (2)

10/45

Calculations:

1. Show working

2. Write the unit for the final answer

Calculate

7/30/2019 Ceramah 2Q (2)

11/45

Diagrams:a. Draw diagrams using a pencil.

b. Draw diagrams to a reasonable size.

c. Make sure that the set-up of the apparatusdrawn works.

d. Label all chemicals in words and label the main

apparatus.

Draw diagrams

7/30/2019 Ceramah 2Q (2)

12/45

Copper atom Tin atom

(a) Draw the arrangement of atoms in bronze, an

alloy of copper.

7/30/2019 Ceramah 2Q (2)

13/45

Copper(II) carbonate

(b) Draw the set-up of the apparatus to investigate the

decomposition of copper(II) carbonate on heating.

7/30/2019 Ceramah 2Q (2)

14/45

(c) Draw the structures of the two isomers of propanol.

propan-1-ol propan-2-ol

7/30/2019 Ceramah 2Q (2)

15/45

Pb2+ + SO42-

PbSO4

Energy

H = -50.4kJ mol -1

(d) Draw the energy level diagram for the reaction

between lead(II) nitrate and sodium sulphate solution.

7/30/2019 Ceramah 2Q (2)

16/45

IMPORTANT DIAGRAMS

The Structure Of Atom

- Determination of melting and boiling point of naphthalene- Particle arrangement in solid, liquid and gas

Chemical Formulae and Equations

- Determination of empirical formula of

magnesium oxide & copper(II) oxide

Periodic Table

- Reactions between chlorine gas and iron

Chemical Bond

- The electron arrangement in ionic and covalent compound.

Sodium chloride/ Magnesium chloride

Tetrachloromethane/ Carbon dioxide

7/30/2019 Ceramah 2Q (2)

17/45

IMPORTANT DIAGRAMS

Electrochemistry

- Electrolysis of molten compound and aqueous solution- Voltaic cell with a salt bridge or a porous pot

Acids and bases

- Reaction between acid and carbonate

- Titration

Salts

- Effect of heating on carbonates and nitrates

Manufactured Substances in Industry

- Comparison of the arrangement of atoms in a pure metal and

an alloy

7/30/2019 Ceramah 2Q (2)

18/45

Common Mistakes Students Make

1. Names of ionsInaccurate Correct

Chlorine ion Chloride ion

Oxygen ion Oxide ion

Hydroxide Hydroxide ion

7/30/2019 Ceramah 2Q (2)

19/45


2. Half-equations

Inaccurate Correct

Mg - 2e Mg2+ Mg Mg2+ + 2e

7/30/2019 Ceramah 2Q (2)

20/45


3. Structure of the Atom

Q: Explain why Q and R are placed in the same period.

[1 mark]

Inaccurate Correct

Atoms of Q and R have the

same number of shells

Atoms of Q and R have the

same number of shells

filled with electrons.

7/30/2019 Ceramah 2Q (2)

21/45


3. Explanation using Collision TheoryQ: Explain how temperature affects the rate of reaction

between zinc and hydrochloric acid. [4 marks]

Inaccurate Correct

At a higher temperature, the

particles move faster.

Collision frequency increases.

Effective collision frequency

increases.Rate of reaction increases.

At a higher temperature, the

particles move faster.

Collision frequency between

zinc atoms and hydrogen

ions increases.Effective collision frequency

increases.

Rate of reaction increases.

7/30/2019 Ceramah 2Q (2)

22/45

Section B

Essay Questions

SPM 2004 B (1)

Diagram 1 shows the chemical symbols which representelements X, Y and Z.

(a) Write the electron arrangement of atoms X and Y.

[2 marks](b) The reaction between atoms of X and Y forms an ionic

compound whereas the reaction between atoms of Y and Z

forms a covalent compound. Explain how these ionic and

covalent compounds are formed. [8 marks]

35

Y17

12

Z6

23

X11

7/30/2019 Ceramah 2Q (2)

23/45

Avoid general answers that do not refer to X, Y or Z.

Inaccurate answer Correct Answer

1(a) X 2:8:1 Y 2:8:7 X 2.8.1 Y 2.8.7(b) - To be stable

- X donates one electron to

form a positive ion

- Y receives one electron toform a negative ion

- To attain stable electron

arrangement/ octet electron

arrangement- Atom of X donates one

electron to form a positive

ion

- Atom of Y receives one

electron to form a negative

ion

7/30/2019 Ceramah 2Q (2)

24/45

Inaccurate answer Correct Answer

-X and Y attract each

other with a strong

electrostatic force

-X+ ion and Y- ion

attract each other with a

strong electrostatic force

7/30/2019 Ceramah 2Q (2)

25/45

Wrong or inaccurate answer Correct Answer

1(b) Y and Z contribute/share 4 pairs of electrons

-Atom of Y and atom of Zshare one pair of

electrons.

-Four atoms of Y shareelectrons with one atom of

Z to form

a molecule with the

formula ZY4.

7/30/2019 Ceramah 2Q (2)

26/45

YY

Y

Y

Z

7/30/2019 Ceramah 2Q (2)

27/45

Section C

A longer answer is usually needed in this section.Part of the questions in this section may involve

experiments.

Do not use formulae or symbols in your

explanations except in writing chemical equations.

All names of chemicals or reagents must be

written in words.All diagrams of set up of apparatus must be

functional, drawn to a reasonable size and labeled.

7/30/2019 Ceramah 2Q (2)

28/45

Use words showing the key action when writing

the procedure of an experiment.

Eg. Add one chemical to anotherStir evenly

Heat gently/ strongly

State quantities used:

Solutions mention volume and concentration

Solids mention a certain mass/ whether an

excess amount should be used

7/30/2019 Ceramah 2Q (2)

29/45

SPM 2003 C(4)(c)

You are required to prepare dry magnesium

chloride salt. Describe a laboratory experiment to

prepare the salt. In your description, include the

chemical equation involved. [10 marks]

Sample answer:

Materials: Magnesium/ magnesium oxide/

magnesium carbonate and dilute hydrochloricacid.

Apparatus: Beaker, filter funnel, filter paper,

Bunsen burner, evaporating dish, glass rod.

Proced re

7/30/2019 Ceramah 2Q (2)

30/45

Procedure:

1. (30-200) cm3 of (0.5 2.0) mol dm-3 hydrochloric

acid is poured into a beaker and heated.2. Magnesium/ magnesium oxide/ magnesium

carbonate is added into the acid and stirred

3. It is added until it is in excess .

4. The mixture is filtered to remove the excess

magnesium/ magnesium oxide/ magnesiumcarbonate.

5. The filtrate is heated in an evaporating dish until

saturated/ concentrated .

7/30/2019 Ceramah 2Q (2)

31/45

6. The saturated solution is left to cool .

7. The mixture is filtered and

8. the crystals are dried between pieces of filter

paper.

Equation:

MgO + 2 HCl MgCl2 + H2O

[Max 10 marks]

7/30/2019 Ceramah 2Q (2)

32/45

CHEMISTRY PAPER 3

Assessment of science process skills.

16 aspects:

Observe (Memerhati)

Classify (Mengelas)Measure (Mengukur menggunakan nombor)

Make inference (Membuat inferens)

Predict (Meramal)

Communicate present information using tables,

graphs etc (Berkomunikasi)

7/30/2019 Ceramah 2Q (2)

33/45

Relate change in a parameter with time (Menggunakan

perhubungan ruang dan masa)

Interpret data (Mentafsirkan data)

Define operationally (Mendefinisi secara operasi)Control variables (Mengawal pembolehubah)

Make a hypothesis (Membuat hipotesis)

Plan an experiment (Mengeksperimen)a. Problem statement

b. Hypothesis

c. Variables

d. Materials and apparatuse. Procedure

f. Tabulation of data

7/30/2019 Ceramah 2Q (2)

34/45

SPM 2010

Plan one laboratory experiment to investigate the

effect of a catalyst on the rate of reaction between

metal and acid. Use copper(II) sulphate solution as

the catalyst. [17 marks]

7/30/2019 Ceramah 2Q (2)

35/45

Problem statement/ Aim, Hypothesis, Variables- can be concluded from the situation given.

Planning an experiment

a) Aim:

To investigate the effect of a catalyst on the rate of

reaction

7/30/2019 Ceramah 2Q (2)

36/45

(b)

Manipulated variable:

Presence of copper(II) sulphate solution

Responding variable:

Rate of reaction

Constant variable:Volume and concentration of sulphuric acid/

mass of zinc

7/30/2019 Ceramah 2Q (2)

37/45

(c) Hypothesis:

The presence of copper(II) sulphate solution increases

the rate of reaction between zinc and dilute sulphuricacid.

7/30/2019 Ceramah 2Q (2)

38/45

Materials and apparatus:

(i) Write separate lists

(ii) State the physical state of substances used

- sodium hydroxide solution, magnesium oxide powder,zinc powder, oxygen gas

(iii) State the correct quantity

- Volume[20 - 200 cm3] HCl

- Mass (solid)[ 2-5 g zinc power]

- concentration[0.5-2.0 mol dm-3]


7/30/2019 Ceramah 2Q (2)

39/45

(d) Substances:

Zinc strip, 0.5 mol dm-3 sulphuric acid, 0.5 mol dm-3

copper(II) sulphate solution

Apparatus:

Conical flask [150 250] cm3, measuring cylinder,

sandpaper, ruler, stopwatch

7/30/2019 Ceramah 2Q (2)

40/45


Procedure:

Steps taken must include apparatus and quantity of

materials.

(e) Procedure:

7/30/2019 Ceramah 2Q (2)

41/45

(e) Procedure:

1.Measure 5 cm of zinc strip and clean

with sandpaper.2. Place zinc strip in a conical flask.

3. Measure 25 cm3 of 0.5 mol dm-3 sulphuric

acid with a measuring cylinder.

4. Pour the sulphuric acid into the conical

flask and start the stopwatch immediately.

7/30/2019 Ceramah 2Q (2)

42/45

5. Swirl the conical flask and record the

time taken for the zinc strip to completely

react with the acid.6. Repeat steps 1 to 5 by adding 20 cm3 of

0.5 mol dm-3 copper(II) sulphate solution.

7/30/2019 Ceramah 2Q (2)

43/45

Tabulation of Data

(i) The number of columns and rows is determined by

the manipulated variable and responding variable.

(ii) Units (if related) must be written for all the titles(iii) Do NOT write the observation, inference or

conclusion in the table.

Communicate

(f) T b l i f D

7/30/2019 Ceramah 2Q (2)

44/45

Experiment Time taken/ s

5 cm zinc+ 25 cm3 of 0.5 mol dm-3 sulphuric acid

5 cm zinc+ 25 cm3 of 0.5 mol dm-3 sulphuric acid

+ 20 cm3 of 0.5 mol dm-3 copper(II)

sulphate solution

(f) Tabulation of Data

7/30/2019 Ceramah 2Q (2)

45/45

Prepared by:

Lee Sok Yan

SMK Damansara Utama

Time is like a river.

You cannot touch the same water twice,

because the flow that has passed

will never pass again.

ceramah 2q (2)

Documents