Page 40 - Ranger SPM 2022 Chemistry

Answers
Jawapan

10. Making a conclusion
Form 4 11. Preparing a report
Penerbitan Pelangi Sdn Bhd. All Rights Reserved.
(c) (i) Calcium carbonate (eggshells) and
acetic acid
CHAPTER 1 Introduction to Chemistry (ii) Colourless gas bubbles are formed
(iii) Manipulated variable: Mass of eggshells
Responding variable: Quantity of gas
Quiz Page 2 bubbles produced
Manipulated variable and responding variable Fixed variable: Type of eggshell
Quiz Page 3 Section C
Face mask Field Example
SPM PRACTICE Food • Acetic acid is used as vinegar
Objective Questions • Sucrose as sugar
1. A 2. C 3. A 4. A 5. C
6. C 7. D 8. B Medicine • Penicillin as antibiotics
Subjective Questions • Propanol as antiseptics
Section A Industry • Copper in wires
• Ceramics in construction materials
1. (a) Does water show the alkaline property of
toothpaste? Agriculture • Urea in fertilisers
(b) Manipulated variable: Presence of water • Calcium hydroxide is used to
Responding variable: Colour change on the neutralise acidic soil
red litmus paper
Fixed variable: Type of toothpaste (b) (i) • Inform the teacher immediately
(c) When water is present, the red litmus paper • Clean the eye with water
turns blue. • To dilute the acid and reduce injury in
(d) • Dry blue litmus paper remains blue the eye
• Dry red litmus paper remains red • Remove laboratory coat immediately
• Moist blue litmus paper remains blue • Shower the body if the acid wets the
• Moist red litmus paper turns blue clothes
[Any three answers] (ii) • Many chemicals burn easily and they
(e) Toothpaste dissolves in water to form are poisonous.
hydroxide ions. • Prevent chemical pollution
Presence of hydroxide ions causes the moist • Reduce the risk of death
red litmus paper turns blue.
Section B
2. (a) • Reactive substances (Li, Na, K) must be CHAPTER 2 Matter and the Atomic
stored in paraffin oil. Structure
• Flammable and volatile hydrocarbons and
organic solvents are kept far from heat Quiz Page 8
sources or sunlight. Condensation
• Corrosive substances (pH < 5 or pH > 9) SPM PRACTICE
must be locked in the cabinet.
• Substances that decompose easily are Objective Questions
stored in a dark place. 1. A 2. A 3. C 4. D 5. C
(b) 1. Making observations 6. C 7. B
2. Making an inference Subjective Questions
3. Identifying the problem Section A
4. Making a hypothesis 1. (a) 3
5. Identifying the variables (b) Natural abunandce is the percentage of
6. Controlling the variables isotopes in a natural sample of an element.
7. Planning an experiment (c) 24 Mg, Mg, Mg
25
26
12
8. Collecting data (d) 12 12 12
9. Interpreting data
235

ANS RANGER SPM CHEMISTRY 2P.indd 235 29/03/2022 2:55 PM