Grade 8 Science Test Answer Key with

Apuntes

Grade 8 Science Test Answer Key with Explanations Question 1 Correct Answer: D) a substance made up of two or more elements that are chemically combined Explanation: A compound is defined as a substance composed of two or more different elements that are chemically bonded together. This means the elements are combined in a specific way that changes their properties. For example, water (H ₂ O) is a compound made of hydrogen and oxygen atoms chemically bonded together. Question 2 Correct Answer: C) They are explanations of scientific events that may change based on continuous research. Explanation: Scientific theories are comprehensive explanations of natural phenomena based on a large body of evidence. Unlike common misconceptions, theories are not just guesses. They can be modified or even replaced as new evidence emerges from ongoing research. For instance, the theory of plate tectonics has evolved significantly since it was first proposed, as scientists have gathered more data about Earth's crust movements. Question 3 Correct Answer: B) Plants grew leaves in the spring and lost leaves in the fall. Explanation: The graph shows a cyclical pattern in CO ₂ levels over two years. CO...