Name: _____________________________________ Block: ______________ Date: _____________________ Chapters 12 & 13 Test– Matter and Its Changes - RETAKE!!! Directions: For the multiple choice questions, choose the best answer to the question and write the letter in the box. EXPLAIN why the correct answer is correct! For the problems that require calculations, show ALL work, including units. LT 12.1: The Structure of the Atom 1. Atoms with the same atomic number but different atomic mass are called: A) charged EXPLAIN!!! B) positive C) isotopes D) ions 2. An element has 13 protons, 16 electrons, and 14 neutrons. To answer all questions, use only this information and not your Periodic Table. a. What is the atomic number of this atom? __________________________ b. What is the atomic mass of this atom? __________________________ c. What is the overall charge of this atom? __________________________ 3. Which force keeps the electrons within in an atom, instead of repelling away from one other? A) static force EXPLAIN!!! B) strong nuclear force C) friction force D) electromagnetic force 4. Which force holds the protons together in an atom? A) static force EXPLAIN!!! B) strong nuclear force C) friction force D) electromagnetic force 5. What part of an atom did J.J. Thompson discover? A) Proton EXPLAIN!!! B) Neutron C)Electron D) Nucleus 6. What part of an atom did Ernest Retherford discover? A) Proton EXPLAIN!!! B) Neutron C)Electron D) Nucleus 7. Why are electrons not included in the mass of an atom? Be specific and clear! 8. What is the most abundant isotope of bromine and how do you know? LT 12.2: Electrons 9. Draw a neutral Boron-11 (B-11) atom with the correct amounts of protons, neutrons, and electrons. Label the following: nucleus, protons, neutrons, and electrons. 10. True/False – place a T for true and an F for false in the blank. _______ Electrons are able to move from level 2 to level 3. _______ All energy levels must hold the same number of electrons. _______ Electrons fill lower energy levels before higher ones. _______ Electrons can stay between energy levels 2 and 3. EXPLAIN!!! EXPLAIN!!! EXPLAIN!!! EXPLAIN!!! 11. Show how the electrons of a neutral Aluminum atom are arranged in energy levels, according to the Bohr model. 12. Identify the following element (each black circle represents an electron): _______________________ EXPLAIN HOW YOU KNOW YOUR ANSWER! LT 12.3: The Periodic Table 13. The tile to the right represents an element from the Periodic Table: a. Which element does it represent? ___________________ EXPLAIN!!! b. How many neutrons does the atom have? ____________ EXPLAIN!!! 14. On most periodic tables, a single atomic mass is listed instead of the mass numbers for all the stable isotopes. How is this mass related to the different isotopes? Be specific and clear. 15. Answer the following questions in regards to Bromine. d. What is Bromine’s atomic #? __________________________ e. What is Bromine’s atomic mass? __________________________ f. What group of the periodic table is Bromine in? __________________________ g. What period of the periodic table is Bromine in? __________________________ h. What is one characteristic of Bromine (cannot be numbers found on the Periodic Table)? __________________________ 16. List two characteristics of either the alkali metals OR the halogens. Clearly state which group you are describing. LT 12.4: Properties of the Elements 17. The repetition of chemical and physical properties of the elements is called: A) commonality. EXPLAIN!!! B) orbitality. C) periodicity. D) columnicity. 18. The majority of elements are in which phase when they are at room temperature? A) Solid EXPLAIN!!! B) Liquid C) Gas D) Plasma 19. For the following questions write the symbol of an element in the blank and circle the reason why. a. An example of an element that is a good conductor is _____________ because it's a (circle) metal non-metal b. An example of an element that is a good insulator is ______________ because it's a (circle) metal non-metal LT 13.1: Chemical Bonds and Electrons 20. Ionic bonds form: A) between oppositely charged atoms. B) molecules. C) by sharing electrons. D) only between nonmetal atoms. EXPLAIN!!! 21. How many valence electrons are in an atom of aluminum, atomic number 13? A) 1 EXPLAIN!!! B) 2 C) 3 D) 4 22. Which of the following is TRUE for valence electrons? A) Valence electrons are always located in the innermost energy level. B) Valence electrons may be lost or gained by an atom when bonding with another atom. C) Each element in the periodic table has a different number of valence electrons. D) Valence electrons are found only in ions. EXPLAIN!!! 23. Explain why noble gases do not form bonds with other elements. Be specific. 24. Explain the difference between ionic and covalent bonding. (Do not just give the definition of each type; you are explaining the difference.) LT 13.2: Chemical Formulas 25. Calcium has an oxidation number of +2, because when it becomes an ion it _____________________. A) gains two electrons. EXPLAIN!!! B) loses two electrons. C) gains two protons. D) loses two protons. 26. What is the oxidation number of manganese (Mn) in the compound, MnO2, if oxygen (O) has an oxidation number of -2? A) - 4 EXPLAIN!!! B) - 2 C) 0 D) + 4 27. How many atoms of Phosphorus and Oxygen are in the compound CaCO3? Ca: O: 28. Write the chemical formula for the compound formed by combining sodium (Na) and oxygen (O). 29. Name the compound formed by combining sodium (Na) and oxygen (O). 30. Determine whether the following compounds are ionic or covalent: C3H8 ___________________________ K2S __________________________