3. What is the factor than can change or be changed in an experiment? A Conclusion B. Data C. Hypothesis D. Variable 4. What is the term for an educated guess in scientific investigation? A. Application B. Experiment C.Hypothesis D. Problem 5. Which of the following substances is an element? A. ammonia B. carbon dioxide C. oxygen D. water 6. Which of the following substances is a compound? A air B. chlorine C. iron D. water 7. What pure substance contains two or more elements chemically bonded together? A, element B. compound C. mixture D. all of the above 8. Which of these is the smallest particle? A. atom B. element C. molecule D. speck of dust 9. Which of these is the correct symbol for calcium? A. C B. Ca C. Co D. Cu 10. What pure substance consists of one type of atom? A, element B. compound C, mixture D. all of the above 11. Which of the following elements is a nonmetal? A aluminum B. carbon C. iron D. lead 12. What do you call the table where elements are organized according to increasing atomie aubers? A. Chemistry Element Table C. Octet Table B. Mendeleev's Table D. Periodic Table of Elements 13. What is a mixture? A. It is a chemically combined substance. B. It is a combination of elements to make a new substance. C. It is a combination of substances where new substances are formed through a reaction D. It is a combination of substances in which the atoms of the substance do not chernically combine. 14. Which of the following examples of matter is a mixture? A. air B. copper C. salt D. vinegar
