Science Grade 8 Past Paper 2022-2023 PDF

# REPUBLIC OF SOMALILAND ## MINISTRY OF EDUCATION ### SOMALILAN NATIONAL EXAMINATION BOARD #### GRADE EIGHT CERTIFICATE EXAMINATION # SCIENCE ## 2022 - 2023 ## TIME 2 HOURS ### Plus 10 minutes for reading through the paper ### INSTRUCTIONS TO CANDIDATES This paper consists of 09 printed pages. C...

# REPUBLIC OF SOMALILAND ## MINISTRY OF EDUCATION ### SOMALILAN NATIONAL EXAMINATION BOARD #### GRADE EIGHT CERTIFICATE EXAMINATION # SCIENCE ## 2022 - 2023 ## TIME 2 HOURS ### Plus 10 minutes for reading through the paper ### INSTRUCTIONS TO CANDIDATES This paper consists of 09 printed pages. Count them now. Inform the invigilator if there are any pages missing. There are two parts. | PART | DESCRIPTION | MARKS | |---|---|---| |**PART 1:** | 20 Multiple Choice | **40** | |**PART 2:** | 10 Structured Questions | **60** | |**TOTAL:** | | **100** | - Answer ALL questions in Part 1 and 2. - Extra papers and Mobile Not Allowed. # Part One: Multiple Choice Questions (40 marks) 1. Bacteria can reproduce very rapidly, especially when the environment is: - a. Warm and moist. - b. Cold and dry. - c. Hot and moist - d. Hot and not moist. 2. Which one of the following diseases is NOT sexually transmitted? - a. Syphilis - b. Gonorrhea - c. AIDS - d. Diarrhea 3. Study the following diagram. Which letter indicates the umbilical cord? - a. L - b. M - c. N - d. O Diagram: A circle with the following letters marked around the outside: - Top: W - Right: L - Bottom: N - Left: M A line pointing from the middle of the circle to the letter M. 4. Fish can be classified into: - a. Cartilage fish and bony fish. - b. Bony fish and tendon fish - c. Tendon fish and cartilage fish - d. Bony fish and muscle fish 5. Study the following diagram. Which number shows the stomata? - a. 1 - b. 2 - c. 3 - d. 4 Diagram: A diagram of a plant leaf with the following numbers marked: - Top: 3, 4 - Right: 1 - Bottom: 2 6. The chemical symbol for Sodium ion is: - a. Na. - b. Na+ - c. Na- - d. N. 7. Bases turn the color of red litmus paper to: - a. Blue. - b. Red. - c. Yellow. - d. Green. 8. When two nonmetals react, what chemical bond do they form? - a. Covalent bond - b. Ionic bond - c. Metallic bond - d. Hydrogen bonds 9. What is the unit of measurement for speed? - a. m/s2 - b. m/s3 - c. m/s - d. s/m 10. Electromagnetism can be used to make: - a. Door bells - b. Hammers. - c. Pulleys. - d. Scissors 11. The band of seven colours of rainbow is called: - a. Spectrum. - b. Prism - c. Lens. - d. Bektrum. 12. Which one of the following expands on heating? - a. Iron sheet. - b. Wooden table. - c. Book. - d. Clothes. 13. Which nutrient is essential for the growth of our body? - a. Protein. - b. Fats. - c. Carbohydrates - d. Minerals. 14. Human heart is a fist-sized organ and the average adult human heart weighs about: - a. 700g - b. 500g - c. 200g - d. 300g 15. What gives you the atomic mass? - a. The number of protons and the number of electrons - b. The number of protons. - c. The number of neutrons - d. The number of protons and the number of neutrons 16. Which one of the following is a good conductor of heat? - a. Iron. - b. Clothes. - c. Plastics. - d. Milk. 17. Light travels in: - a. Zigzag line - b. Straight line - c. Knotted line - d. Intermittent line 18. Which one of the following is the most common source of air pollution? - a. Oxygen gas. - b. Carbon dioxide. - c. DDT. - d. Nitrogen. 19. The following diagram indicates? - a. Thread worm. - b. Gunaya worm - c. Tape worm. - d. Hookworm. Diagram: A drawing of an elongated worm with a pointed head. 20. What type of reaction is burning a piece of a paper in the air? - a. Physical reaction - b. Mixture reaction - c. Chemical reaction - d. Balanced reaction # Part Two: Structured Questions (60 marks) 1. a) Write down four characteristics of HIV AIDS? (2 marks) - i. - ii. - iii. - iv. b) How can HIV/AIDS be controlled? (2 marks) c) How is HIV/AIDS passed from one person to another? (2 marks) 2. a) Define photosynthesis. (2 marks) b) Complete the following chemical equation. (2 marks) Carbon dioxide + water —> _ + _ c) What happens in the dark phase (level) of photosynthesis? (2 marks) Diagram: A circle with the following labels marked around the outside: - Top: Light phase - Bottom: Dark phase 3. Study the following diagram. Atom Y has an electronic configuration (arrangement) of 2.8.1. Write down: - a) The name of atom Y. (2 marks) - b) The number of electrons in the upper most shell. (2 marks) - c) The chemical symbol of atom Y. (2 marks) Diagram: A circle with the letter "Y" in the middle. 4. Write down chemical six properties of bases. (6 marks) - a) - b) - c) - d) - e) - f) 5. Match the element with symbols with their chemical symbol: (6 marks) | Elements | Symbols | |---|---| | 1 Carbon | | | 2 Iron | | | 3 Copper | | | 4 Oxygen | | | 5 Potassium | | | 6 Neon | | Key: - Ne - K - O - C - Fe - Cu 6. Write down three appliances or devices that use electromagnets. (6 marks) - a) - b) - c) 7. a) Define Speed. (2 Marks) b) How long will it take if an object travels 150m with an average speed of 40m/s? (2 Marks) c) Convert 1500m into kilometers. (2 marks) 8. What happens to light when it hits different objects? (6 Marks) - a. Transparent object - b. An opaque object - c. Translucent object 9. Write down the functions of the following blood cells. (6 marks) | Blood cells | Functions | |---|---| | 1 Red blood cells | | | 2 Platelets | | | 3 White blood cells | | 10. a) How do tapeworms spread in humans? (2 marks) b) How to control tapeworms? (2 marks) c) Where do tapeworms attach to in the digestive system? (2 marks)