11. The bright-line spectra produced by four elements are represented in the diagram below.

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1 1. Which substance can not be broken down by a chemical change? A) ammonia B) ethanol C) propanal D) zirconium 2. Which particle has no charge? A) electron B) neutron C) positron D) proton 3. Which phrase describes an atom? A) a negatively charged nucleus surrounded by positively charged protons B) a negatively charged nucleus surrounded by positively charged electrons C) a positively charged nucleus surrounded by negatively charged protons D) a positively charged nucleus surrounded by negatively charged electrons 4. An ion that consists of 7 protons, 6 neutrons, and 10 electrons has a net charge of A) 4 B) 3 C) 3+ D) As a result of the gold foil experiment, it was concluded that an atom A) contains protons, neutrons, and electrons B) contains a small, dense nucleus C) has positrons and orbitals D) is a hard, indivisible sphere 6. Which electron configuration represents the electrons in an atom of Ga in an excited state? A) B) C) D) Which quantity represents the number of protons in an atom? A) atomic number B) oxidation number C) number of neutrons D) number of valence electrons 8. What is the charge of the nucleus of an oxygen atom? A) 0 B) 2 C) +8 D) The notation for the nuclide Cs gives information about A) mass number, only B) atomic number, only C) both mass number and atomic number D) neither mass number nor atomic number 10. A bromine atom in an excited state could have an electron configuration of A) B) C) D)

2 11. The bright-line spectra produced by four elements are represented in the diagram below. Given the bright-line spectrum of a mixture formed from two of these elements: Which elements are present in this mixture? A) A and D B) A and X C) Z and D D) Z and X 12. The bright-line spectrum of sodium is produced when energy is A) absorbed as electrons move from higher to lower B) absorbed as electrons move from lower to higher C) released as electrons move from higher to lower D) released as electrons move from lower to higher 13. Which list includes elements with the most similar chemical properties? A) Br, Ga, Hg B) Cr, Pb, Xe C) O, S, Se D) N, O, F 14. The elements in Group 2 are classified as A) metals B) metalloids C) nonmetals D) noble gases 15. At STP, which element is solid, brittle, and a poor conductor of electricity? A) Al B) K C) Ne D) S 16. As the elements is Period 3 are considered in order of increasing atomic number, there is a general decrease in A) atomic mass B) atomic radius C) electronegativity D) first ionization energy

3 17. Which element in Period 3 has the largest atomic radius? A) Cl B) Al C) Na D) P 18. Which element has atoms with the strongest attraction for electrons in a chemical bond? A) chlorine B) nitrogen C) fluorine D) oxygen 19. Which element requires the least amount of energy to remove the most loosely held electron from a gaseous atom in the ground state? A) bromine B) calcium C) sodium D) silver Base your answers to questions 20 through 23 on the information below and on your knowledge of chemistry. A student compares some models of the atom. These models are listed in the table below in order of development from top to bottom. 20. State one way in which the Bohr model agrees with the Thomson model. 21. Using the conclusion from the Rutherford model, identify the charged subatomic particle that is located in the nucleus. 22. State one conclusion about the internal structure of the atom that resulted from the gold foil experiment. 23. State the model that first included electrons as subatomic particles.

4 24. Base your answer to the following question on the following information. Carbon and oxygen are examples of elements that exist in more than one form in the same phase. Graphite and diamond are two crystalline arrangements for carbon. The crystal structure of graphite is organized in layers. The bonds between carbon atoms within each layer of graphite are strong. The bonds between carbon atoms that connect different layers of graphite are weak because the shared electrons in these bonds are loosely held by carbon atoms. The crystal structure of diamond is a strong network of atoms in which the shared electrons are strongly held by the carbon atoms. Graphite is an electrical conductor, but diamond is not. At 25 C, graphite has a density of 2.2 g/cm 3 and diamond a density of 3.51 g/cm 3. The element oxygen can exist as diatomic molecules, O2, and as ozone, O3. At standard pressure the boiling point of ozone is 161 K. Calculate the volume, in cm 3, of a diamond at 25 C that has a mass of gram. Your response must include both a correct numerical setup and the calculated result. 25. The modern model of the atom is based on the work of A) one scientist over a short period of time B) one scientist over a long period of time C) many scientists over a short period of time D) many scientists over a long period of time 26. Given the diagram representing a process being used to separate the colored dyes in food coloring: Which process is represented by this diagram? A) chromatography B) electrolysis C) distillation D) titration 27. Which nuclear emission has the greatest mass and the least penetrating power? A) an alpha particle B) a beta particle C) a neutron D) a positron 28. An unstable nucleus loses the most mass if the nucleus emits A) an alpha particle B) a beta particle C) a positron D) a gamma ray 29. Compared to the mass and the penetrating power of an alpha particle, a beta particle has A) less mass and greater penetrating power B) less mass and less penetrating power C) more mass and greater penetrating power D) more mass and less penetrating power 30. Which particle has the least mass? A) alpha particle B) beta particle C) neutron D) proton 31. Which nuclear emission has the greatest penetrating power? A) alpha particle B) beta particle C) gamma radiation D) positron 32. Which statement explains why nuclear waste materials may pose a problem? A) They frequently have short half-lives and remain radioactive for brief periods of time. B) They frequently have short half-lives and remain radioactive for extended periods of time. C) They frequently have long half-lives and remain radioactive for brief periods of time. D) They frequently have long half-lives and remain radioactive for extended periods of time. 33. The decay of which radioisotope can be used to estimate the age of the fossilized remains of an insect? A) Rn-222 B) I-131 C) Co-60 D) C-14

5 34. Element X has two isotopes. If 72.0% of the element has an isotopic mass of 84.9 atomic mass units, and 28.0% of the element has an isotopic mass of 87.0 atomic mass units, the average atomic mass of element X is numerically equal to A) B) C) D) 35. As an electron moves from a 3s orbital to a 2s orbital, the energy of the atom A) decreases B) increases C) remains the same