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Name:______________________________________________________ Date:________________________ Block:_______ GRADE 8 SCIENCE SOL QUESTIONS: 2003, 2004, 2005 1. Which process is a physical change? a. Rusting iron b. Burning coal c. Tarnishing silver d. Melting ice _ 2. When a base is mixed with an acidic solution, neutralization occurs because the — a. base reaches absolute zero b. acid evaporates c. base chemically reacts with the acid d. mass of the solution increases 3. Because zinc can combine with other substances but cannot be changed into a simpler substance by an ordinary chemical process, zinc is classified as — a. a compound b. a mixture c. an element d. an acid 4. In the chemical formula for ammonia, NH3, what does the subscript 3 represent? a. The number of nitrogen and hydrogen atoms in each molecule of ammonia b. The number of hydrogen atoms in each molecule of ammonia c. The number of ammonia molecules that will bond together d. The number of nitrogen atoms in each molecule of ammonia 5. Which instrument would most accurately and precisely determine the mass of a toy car? a. An electronic light meter b. A spring scale c. A triple-beam balance d. A graduated cylinder 6. The diagram above shows a block from the periodic table. The number six represents the a. atomic mass of the element carbon b. atomic number of the element carbon c. number of neutrons in the element carbon d. number of valence electrons in the element carbon 7. A mixture of iron filings and sulfur can easily be separated by — a. placing the mixture in water b. performing a chemical reaction c. heating the mixture d. using a magnet 8. Of the states of matter, gas is the only state that — a. is fluid b. has mass c. is highly compressible d. has a definite shape 9. Which of these is best classified as a mixture? a. Carbon dioxide b. Water c. Soil d. Iron 10. Which of these belongs in the outermost shell (energy level) of an atom? _ a. Electrons b. Protons c. Neutrons d. Photons 11. A substance made up of two or more elements that have been chemically combined is called — a. an atom b. a compound c. an element d. a mixture 12. A proton has which of the following charges? a. Negative b. Neutral c. Positive d. Magnetic 13. Which of the following lists the elements in order, from those having the least protons to those having the most protons in the atoms? a. O, N, B, Li b. Na, S, Al, Cl c. O, S, Se, Te d. Rb, K, Na, Li 14. Calcium metal (Ca) can be produced by passing an electric current through molten calcium chloride (CaCl2). Chlorine gas (Cl2) is also formed. What is the balanced equation for this reaction? a. 2CaCl Ca + 2Cl b. CaCl2 + H2O Ca + ClH + O2 c. CaCl2 + Cl Ca + Cl3 d. CaCl2 Ca + Cl2 Name:______________________________________________________ Date:________________________ Block:_______ 15. The density of an object is dependent upon the object’s mass and — a. height b. area c. volume d. weight 22. Which of these is a change in chemical composition? a. A lake freezes solid. b. Gravel, sand, and water are mixed. c. A copper bar is rolled into a flat sheet. d. Vinegar bubbles when baking soda is added. 16. Which of these will cause water to change to ice? a. Removing heat from the water b. Stirring the water c. Adding salt to the water d. Putting the water in the sunlight 23. Which of these elements has an atomic number of 14? a. N b. Al c. Si d. P 17. Which of the following elements belongs to the family indicated? a. Nitrogen belongs to the halogen family. b. Helium belongs to the noble gas family. c. Calcium belongs to the alkali family. d. Sodium belongs to the alkaline earth family 24. Tearing paper is an example of a —_ a. physical change b. chemical change c. chemical reaction d. solution 18. The atom is composed of electrons, protons, and neutrons. What is the electric charge on the neutron? a. -1 b. 1 c. 0 d. -2 19. Several centuries ago, men called alchemists tried to transform common metals into gold. Even though they tried many different chemical and physical methods, they never succeeded because — a. they could not heat common metals to extremely high temperatures b. the common metals they worked with were not pure c. they did not add the correct material to the common metal d. elements cannot be changed to other elements by physical or chemical means 20. Mercury is a liquid metal that is used in many thermometers. The mercury in the thermometer rises because it — a. is sucked upward by vacuum b. expands when heated c. is compressed by air pressure d. increases in density when heated 21. Which of the following is a physical property of copper? a. Ductile, can be drawn into a wire b. Liquid at room temperature c. Readily reacts with water to form an acid d. Readily reacts with oxygen