Monday, May 31, 2010
Tuesday, May 11, 2010
TIPS for Form 5
Paper 2
Section A - 6 Questions - answer all
Section B - 2 questions - compulsory to answer any 1 question
Section C - 2 questions - compulsory to answer any 1 question
Paper 3
Q 1 - structure question
Q2 - structure question
Q3 - planning of experiment
Topics to study:(paper 2 +3)
1.structure of atom / periodic table
- electron arrangement, period, group, size, electronegativity, melting/boiling point, ionic/covalent bond -draw the formation.
2. electrolytic cell / voltaic cell
3. carbon compounds - homologous series - reactions of alkene, alcohol and carboxylic acid
4. salt - preparation of soluble salt (not K, Na and ammonium), heating of salt, gas test etc.
5. heat of neutralisation
6. heat of combustion
7. Rate of reaction - temperature, catalyst, concentration
8. using collision theory to explain the rate of rection
9.formation of ionic and covalent compound - draw and explain.
10.pH and acid.
11.exothermic and endothermic reaction.
12. construct the ECS using different metals.
TIPS for Form 4
Paper 2
Section A - 6 Questions - answer all
Section B - 1 question - compulsory to answer
Section C - 1 question - compulsory to answer
Paper 3
Q 1 - structure question
Q2 - structure question
Q3 - planning of experiment
Important topics to study:
1. Periodic Table - name, group, period, characteristic ...
2. chemical formula - **emiprical formula and molecular formula - calculation - experiment
3. structure of atom - proton, neutron, elektron, etc...
4. chemical formula and equation - calculation
5. reaction of alkali metals - with oxygen, water and halogen - reactivity
6. reaction of halogen - with water, iron - reactivity
7. formation of ionic/covalent compound - explain in details - drawing.
** very important.
Sample Question For Paper 3
“When lithium metal is put in water, it moves very slowly on the surface of the water. When sodium metal is put in water, it moves quite fast and produces “hiss” sound. When potassium metal is put in water, it moves very fast and produces small explosions”.
Plan an experiment in the laboratory to investigate the reactivity of lithium, sodium and potassium with water. The planning of your experiment must consist of the following:
(a) Aim of experiment
(b) Statement of the hypothesis
(c) All the variables
(d) List of substances and apparatus
(e) Procedure of the experiment
(f) Tabulation of data
[17 marks]
Please try this question, I'll upload the answer soon.
Sample Answer:
| Aim | To determine the reactivity of alkali metals with water. | ||||||||
| Problem statement | How do Group 1 elements do reacts with water? | ||||||||
| Variables | MV: Different types of alkali metals RV: Reactivity of alkali metals FV: size of alkali metals | ||||||||
| Hypothesis | Alkali metals become more reactive in reaction with water when going down Group 1. | ||||||||
| Apparatus & Materials | A: forceps, knife M: small piece of lithium, sodium, potassium, filter paper, distilled water. | ||||||||
| Procedure | 1. Cut a small piece of lithium using forceps and knife. 2. Dry the oil on the surface of lithium with filter paper. 3. Place the lithium on the surface of water in a trough. 4. Record the reactivity of lithium with water. 5. Repeat steps 1 to 4 using potassium and sodium. | ||||||||
| Tabulation of data |
|
Wednesday, May 5, 2010
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