1. EXAM REVISION QUESTIONS YEAR 9 SCIENCE

2. Chapter 1: Investigating Reactions
Define endothermic and exothermic.
Cold packs are often used to treat sports injuries. When the pack is bent, two chemicals are mixed together causing it to become cold. Using the word energy in your answer, explain why the pack goes cold.

3. Chapter 1: Investigating Reactions
Define endothermic reaction and exothermic reaction.
An endothermic reaction is one where some form of energy must be supplied.
An exothermic reaction is one that releases energy (usually in the form of heat, but sound, light and electrical energy can also be produced).
Cold packs are often used to treat sports injuries. When the pack is bent, two chemicals are mixed together causing it to become cold. Using the word energy in your answer, explain why the pack goes cold.
When the pack is broken, an endothermic reaction occurs, taking heat from the surroundings and making the pack feel cold.

4. Chapter 8: Living with Acids and Bases
A quick way to find out whether a solution is acidic or basic is to use an indicator. Using the indicator colour chart in your text book, suggest an approximate pH for the solutions below:
- Solution X containing methyl orange that is coloured pink.
- Solution Y containing universal indicator that is coloured green.
- Solution Z containing methyl orange and phenol red that is coloured pale orange.
An acid is defined as a substance which:
Releases OH- ions in solution
Releases H+ ions in solution
Releases hydrogen atoms in solution
Absorbs H+ ions from solution.

5. Chapter 8: Living with Acids and Bases
- Solution X containing methyl orange that is coloured pink.
- Solution Y containing universal indicator that is coloured green.
- Solution Z containing methyl orange and phenol red that is coloured pale orange.
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6. Chapter 8: Living with Acids and Bases
An acid is defined as a substance which:
Releases OH- ions in solution
Releases H+ ions in solution
Releases hydrogen atoms in solution
Absorbs H+ ions from solution.
Page 285 (Glossary)

7. Chapter 8: Living with Acids and Bases
A quick way to find out whether a solution is acidic or basic is to use an indicator. Using the indicator colour chart in your text book, suggest an approximate pH for the solutions below:
- Solution X containing methyl orange that is coloured pink. pH = 1
- Solution Y containing universal indicator that is coloured green. pH = 8
- Solution Z containing methyl orange and phenol red that is coloured pale orange. pH = 5
An acid is defined as a substance which:
Releases OH- ions in solution
Releases H+ ions in solution
Releases hydrogen atoms in solution
Absorbs H+ ions from solution.

8. Chapter 7: Everyday Substances
Alloys are best described as:
A mixture of a metal and another metal.
A mixture of a metal and a non-metal.
A compound formed from a metal and a non-metal.
A compound formed from a metal and another metal.
List the five main methods that are used to stop iron from rusting, and give an example for each method.

9. Chapter 7: Everyday Substances
Alloys are best described as:
A mixture of a metal and another metal.
A mixture of a metal and a non-metal.
A compound formed from a metal and a non-metal.
A compound formed from a metal and another metal.
Page 150

10. Chapter 7: Everyday Substances
List the five main methods that are used to stop iron from rusting, and give an example for each method.
Painting – steel exposed to weather
Coating with oil, grease or tar – bike chains, inside of car engine
Coating with plastic – garden chairs, dish racks, tennis courts and inside of steel cans
Coating with metal – food storage, bumper bars, cutlery
Sacrificial protection – galvanised iron
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11. Chapter 4: Living with Microbes
Write a definition for phagocyte and state its role in the body for fighting disease.
Microbes such as bacteria, viruses, fungi and protozoa can cause diseases. State what type of microbe causes each of the diseases below: (Hint: you may need Google to help you or ask someone who researched one of these diseases for their literacy task!)
Chicken pox
Tetanus
Athlete’s foot
Malaria
Pneumonia

12. Chapter 4: Living with Microbes
Write a definition for phagocyte and state its role in the body for fighting disease.
A phagocyte is a large white blood cell. The engulf and destroy microbes that cause disease.
Microbes such as bacteria, viruses, fungi and protozoa can cause diseases. State what type of microbe causes each of the diseases below: (Hint: you may need Google to help you or ask someone who researched one of these diseases for their literacy task!!!)
Chicken pox virus
Malaria protozoa
Tetanus bacteria
Pneumonia bacteria or virus
Athlete’s foot fungi
Page 95

13. Chapter 2: Light and Sound
State the Law of Reflection.
Light enters the eye through the pupil. If a person walks from dull light into bright light, what will happen to the size of the pupil?
The pupil will get thinner
The pupil will get fatter
The pupil will go from small to large
The pupil will go from large to small
The pupil will not change size at all

14. Chapter 2: Light and Sound
State the Law of Reflection.
Angle of incidence = angle of reflection
Light enters the eye through the pupil. If a person walks from dull light into bright light, what will happen to the size of the pupil?
The pupil will get thinner
The pupil will get fatter
The pupil will go from small to large
The pupil will go from large to small
The pupil will not change size at all
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