Question: Identify the element that has an atomic number of 15.

1. oxygen

2. B. phosphorus

3. C. silicon

4. D. sulfur

5. Answer: B. phosphorus

6. Question: In a chemical reaction, matter is neither created or destroyed. Which law does this refer to?

7. A. Law of Multiple Proportions

8. B. First Law of Thermodynamics

9. C. Law of Modern Atomic Theory

10. D. Law of Definite Proportions

11. E. Law of the Conservation of Mass

12. Answer: E. Law of the Conservation of Mass

13. Question: The mass number is equal to……?

14. A. the sum of the number of protons, neutrons, and electrons.

15. B. the sum of the number of the electrons and protons.

16. C. the sum of the number of the neutrons and electrons.

17. D. the sum of the number of protons and neutrons.

18. Answer: D. the sum of the number of protons and neutrons.

19. Question: An ion has 8 protons, 9 neutrons, and 10 electrons. The symbol for the ion is ________.

20. A. 19F-

21. B. 17Ne2+

22. C. 17O2+

23. D. 19F+

24. E. 17O2-

25. Answer: E. 17O2-

26. Question: Determine the number of protons, neutrons and electrons in the following:

27. 40

28. 18 X

29. A. p+ = 18 n° = 22 e- = 40

30. B. p+ = 18 n° = 18 e- = 22

31. C. p+ = 40 n° = 22 e- = 18

32. D. p+ = 22 n° = 18 e- = 18

33. E. p+ = 18 n° = 22 e- = 18

34. Answer: E. p+ = 18 n° = 22 e- = 18