Semester II Final Exam Study Questions Answer Key

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1 Semester II Final Exam Study Questions Answer Key Unit 5: Matter Standards: Standard 1: Structure and Properties of Matter All matter is made up of atoms. Its structure is made up of repeating patterns and has characteristic properties. 1. Matter is made up of minute particles called atoms, and atoms are composed of even smaller components (i.e., protons, neutrons, and electrons). 2. An element is identified by the number of protons (atomic number) in the nucleus. a. When elements are listed in order of increasing number of protons, repeating patterns of physical and chemical properties identify families of elements with similar properties. b. Elements found on the earth are also found throughout the universe. 3. Matter has characteristic properties that are unique for pure substances and can be used to separate one substance from another (e.g., boiling points, melting points, density). 4. A compound is formed when two or more kinds of atoms bind together chemically. Each compound is formed when two or more kinds of atoms bind together chemically. Each compound has unique chemical and physical properties. Standard 2: Conservation of Matter Matter is neither created nor destroyed in physical and chemical interactions. 1. Chemical changes are identified by one or more events (i.e., precipitate, color change, gas production, heat gain or loss). Key Terms and Topics: kinetic theory, Kelvin, temperature, thermal energy, heat, specific heat, plasma, heat of fusion, heat of vaporization, substance, element, compound, heterogeneous mixture, homogeneous mixture, solution, colloid, Tyndall effect, suspension, physical property, physical change, distillation, chromatography, chemical property, chemical change, law of conservation of mass Helpful Hints: Know how to convert between Celsius and Fahrenheit. Explain how thermal energy and temperature are related. Calculate the change in thermal energy of an object due to a temperature change.! Chapter 9: page 255; Applying Math, Practice Problem 1-2, page 258; Applying Math, Practice Problem 1, page 259; Section 1 Review #1-7, page 265; Section 2 Review #1-4, page 282; 1-3, 7, 8, 11, 12, 14 Page o C o F Page ,600 J Page Thermal energy transfers from your hand to the block of ice as the particles in your hand strike the particles of ice where your hand touches the ice. 2. Temperature is the average kinetic energy of the particles in the object. Kinetic energy is one of the components of thermal energy. As kinetic energy changes, thermal energy changes. 3. No, the temperature change depends on the specific heat of each material. 4. The particles in matter are constantly moving and colliding with other particles. 5. It is false. Thermal energy depends on the amount of material and the potential energy of the particles in the objects ,184,000 J 7. 1,800 J/(kg o C) Page As the temperature increases, particles move faster on average and become farther apart. The volume occupied by the particles increases but the mass of the particles doesn t change. As a result, the density decreases.

2 substance. 3. When the ice cube melts, the forces between molecules become weaker. 4. The boiling point at sea level is higher. Page Heat 2. Temperature 3. Specific heat 7. D 8. C 11. C 12. D 14. A! Chapter 18: page 558; Section 1 Review #1-4, page 567; Section 2 Review #1-5, page 572; #1-20, page 574; STP 1-6 page Both compounds and homogeneous mixture are made of more than one element and are homogeneous. 2. A substance must be either an element or a compound. Mixtures can be made from combinations of compounds or elements. 3. Colloids do not settle out; suspensions eventually do settle out. Particles in colloids are smaller than particles in suspensions. 4. Materials in suspensions settle out. page The make up of water units is unchanged. 2. color, odor, volume, temperature 3. Because the original materials are changed into new substances. 4. The mass of all the substances present before a chemical change equals the mass of all the substances remaining after the change. 5. Let the ice melt on a balance, and show that the balance doesn t move. page Compounds 2. suspension 3. physical change 4. law of conservation of mass 5. heterogeneous mixture 6. elements 7. physical change

3 9. D 10. B 11. A 12. D 13. D 14. C 15. B 16. A 17. D 18. see class flow chart from Unit see bellringers from Unit Elements and compounds are made from atoms. An element has all the same atoms whereas a compound is made of atoms of two or more elements. An example of an element is Fluorine. An example of a compound is water: H 20. page B 2. C 3. A 4. B 5. A 6. D Unit 6: Atoms Standards: Standard 1: Structure and Properties of Matter All matter is made up of atoms. Its structure is made up of repeating patterns and has characteristic properties. 1. Matter is made up of minute particles called atoms, and atoms are composed of even smaller components (i.e., protons, neutrons, and electrons). 2. An element is identified by the number of protons (atomic number) in the nucleus. a. When elements are listed in order of increasing number of protons, repeating patterns of physical and chemical properties identify families of elements with similar properties. b. Elements found on the earth are also found throughout the universe. Key Terms and Topics: atom, nucleus, proton, neutron, electron, quark, electron cloud, atomic number, mass number, isotope, average atomic mass, electron dot diagram, Democritus, Bohr, Thomson, Dalton, Rutherford Helpful Hints: Identify the names and symbols of common elements. Describe the electron cloud model of an atom. Know the difference between an isotope and an ion.! Chapter 19: page 583; Section 1 Review #1-5, page 587; Section 2 Review #1-5, page 602; 2-5, 7, 8, 14-16, page 604; STP #3, 5, 6

4 2. proton, +1, nucleus; neutron, 0, nucleus; electron, -1, electron cloud 3. quark; by accelerating protons and making them collide with so much force that they broke apart 4. This model says electrons are most likely to be found in a cloud surrounding the nucleus; it is 100,000 times larger than the diameter of the nucleus. 5. The blades on a rotating super fan appear as a smooth metal surface around the center hub. The probability area for electrons in an atom also presents a solid appearance. The fan blades are different from electrons because they are much larger and, when the fan stops, it can easily be seen. page Mass number = 35; atomic number = Isotopes have the same number of protons but different numbers of neutrons. 3. Elements have several isotopes with different numbers of neutrons, and thus different masses. The average atomic mass is the weighted average of the masses of the element s isotopes. 4. Mass number atomic number = number of neutrons = = The average of lies closer to the 35 mass number that to the 37 mass number. page Isotopes 3. average atomic mass 4. nucleus 5. Quarks 7. mass number 8. electron cloud 14. A 15. B 16. B page C 5. C 6. D Unit 7: Periodic Table Standards: Standard 1: Structure and Properties of Matter All matter is made up of atoms. Its structure is made up of repeating patterns and has characteristic properties. 1. Matter is made up of minute particles called atoms, and atoms are composed of even smaller components (i.e., protons, neutrons, and electrons). 2. An element is identified by the number of protons (atomic number) in the nucleus. a. When elements are listed in order of increasing number of protons, repeating patterns of physical and chemical properties identify families of elements with similar properties. b. Elements found on the earth are also found throughout the universe.

5 another (e.g., boiling points, melting points, density). Key Terms and Topics: periodic table, group, family, period, ionization energy, atomic energy, electronegativity, periodic law, Mendeleev, Mosely, metal, nonmetal, metalloid Helpful Hints: Use the periodic table to obtain information. Predict trends on the periodic table (ionization energy, electronegativity, atomic radius, metallic properties).! Chapter 19.3: page 596; Section 3 Review #1-5, page 602; #1, 6, 7, 9, 10-13, page 604; STP #1, 2, 4 page N, nitrogen, 7, ; Ca, calcium, 20, ; Kr, krypton, 36, ; W, tungsten, 74, nitrogen, period 2, group 15; sodium, period 3, group 1; iodine, period 5, group 17; mercury, period 6, group K, potassium, metal; Si, silicon, metalloid; Ba, barium, metal; S, sulfur, nonmetal 4. One could not be certain that the gaps in Mendeleev s table would be filled by only one element. However, Moseley s table was arranged by number of protons (atomic number). Therefore, if the gap were between two elements differing by two protons, only one element could fit. 5. The graph should indicate that about 79% of the elements are metals; about 7% are metalloids, and about 14% are nonmetals. page Periodic table 6. period 7. mass number 9. D 10. C 11. B 12. B 13. A page D 2. D 4. C Unit 8: Chemical Equations Standards: Standard 1: Structure and Properties of Matter All matter is made up of atoms. Its structure is made up of repeating patterns and has characteristic properties. 2. An element is identified by the number of protons (atomic number) in the nucleus. a. When elements are listed in order of increasing number of protons, repeating patterns of physical and chemical properties identify families of elements with similar properties. b. Elements found on the earth are also found throughout the universe. 4. A compound is formed when two or more kinds of atoms bind together chemically. Each compound is formed when two or more kinds of atoms bind together chemically. Each compound has unique chemical and physical properties.

6 1. Chemical changes are identified by one or more events (i.e., precipitate, color change, gas production, heat gain or loss). 2. Chemical equations are used to represent chemical changes in which reactant(s) form product(s). 3. Chemical reactions can be classified (e.g., synthesis/combination, decomposition, single displacement, double displacement). Key Terms and Topics: chemical formula, ion, cation, anion, chemical bond, ionic bond, covalent bond, molecule, polar molecule, nonpolar molecule, metallic bond, binary compound, oxidation number, polyatomic ion, hydrate, chemical reaction, reactant, product, chemical equation, balanced chemical equation, combustion reaction, synthesis reaction, decomposition reaction, single-displacement reaction, double-displacement reaction Helpful Hints: Be able to determine the difference between ionic, covalent, and metallic bonds. Know how to form chemical formulas for both ionic and covalent compounds. Know how to balance chemical equations. Be able to identify the different types of reactions.! Chapter 22: page 692; Section 1 Review #1-4, page 702; Section 2 Review #1-6, page 705; Applying Math Practice Problems #1-2, page 709; Section 3 #1-5, page 714; #1-20, page 716; STP #1-9 page Sodium, as an element, is a solid metal. Chlorine is a gas. When the two combine to form sodium chloride, they form a solid compound. 2. The compound ratio is made up of one barium ion and two fluoride ions. Also, since the compound is made up of a metal and a nonmetal, it is likely ionic. 3. If an element has eight electrons in its outer energy level, it has a tendency to not react because the element is stable. Other elements form compounds as a way to complete their outer energy levels in order to become stable. 4. Hydrogen, carbon, and oxygen are in the compound. Each unit contains 4 hydrogen, two carbon, and two oxygen atoms. page In ionic bonds, one atom accepts electrons from another. This happens only among elements having large differences in their attractions for electrons. 2. In ionic bonds, one atom accepts an electron from another atom. In a covalent bond, electrons are shared, sometimes unequally. 3. Covalent bonding produces molecules. 4. Ask if you would like me to check this question for you 5. Ionic: Ca-O and K-O, because K and Ca are metals far from O on the periodic table; covalent: S-O, because S and O are nonmetals close to each other on the periodic table. 6. The charge on Al is +3 and the charge on ) is [2(+3)] + [3(-2)] = 0. page Pb 3P 4 2. Fe 2O 3 page KI; Mg(OH) 2; Al 2(SO 4) 3; Cl potassium chloride; chromium(iii) oxide; barium chlorate; ammonium chloride; phosphorus trichloride

7 4. Sodium and potassium will bond with atoms that are able to easily accept electrons. They would have a difficult time bonding with each other because both tend to lose electrons. 5. Oxygen contributes 4 X -2 = -8. The total charge is -2, so sulfur must contribute +6. page Polyatomic ion 2. binary compound 3. polar molecule 4. ion 5. ionic bond 6. covalent bond 7. hydrate 8. molecule 9. oxidation number 10. chemical formula 11. B 12. C 13. A 14. C 15. B 16. B 17. A 18. D 19. more stable; different from; ionic; gained and lost; covalent; shared 20. hydrogen sulfide; H 2S page D 2. A 3. A

8 5. A 6. C 7. B ! Chapter 23: page 725; Section 1 Review #1-6, page 729; Section 2 Review #1-6, page 733; Section 3 Review #1-7, page 746; 1, 2, 6-8, 10, 12, 13, 15, page 748; STP # 1, 2, 5 page Reactants; Cd(NO3) 2 and H 2S; products; CdS and HNO 3 2. Zn is a solid, HCl is dissolved in water, H 2 is a gas, and ZnCl 2 is dissolved in water 3. Both reactions produce a change, resulting in a new product. In a chemical reaction, the electrons are rearranged to create new bonds. In a nuclear reaction, the nucleus of the atom is changed. 4. The law of conservation of mass explains what matter in the universe does not go away permanently. 5. Scientists from different countries would have a difficult time discussing discoveries due to lack of a common language = 1,010 g of reactant, which must equal 1,010 g of product; 1010 g 92 g = 918 g of soap. page Conservation of mass requires that the number of atoms of an element on the left side equals the number of atoms on the right side. Balanced equations accurately depict chemical changes. 2. 2Fe + O 2 " 2FeO 3. Oxygen gas exists as a diatomic molecule The coefficients represent the number of units of a compound, not the number of atoms. 6. 2Fe(s) + 3Cl 2(g) " 2FeCl3(s) page a) synthesis b) single displacement c) decomposition 2. A substance combines with oxygen to produce energy. 3. Synthesis involves bringing elements or compounds together. Decomposition involves breaking compounds down. 4. Zinc will displace gold because zinc is more reactive than gold. 5. reduced Cl; oxidized - Na 6. 3Fe(s) + 4H 20(l) " Fe 3O 4(s) + 4H 2(g)

9 page The two are opposite processes; in a synthesis reaction substances are put together and in a decomposition reaction they are taken apart. 2. In a chemical change, reactants change into products. 6. In single-displacement reactions, only one element of one compound is replaced by another element. In doubledisplacement reactions, two elements in two compounds change places. 7. Not all chemical reactions are synthesis reactions, but all synthesis reactions are chemical reactions. 8. D 10. D 12. C 13. D 15. A page D 2. C 5. D