Honors Chemistry: Chapter 4- Problem Set (with some 6)

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1 Honors Chemistry: Chapter 4- Problem Set (with some 6) All answers and work on a separate sheet of paper! Classify the following as always true (AT), sometimes true (ST), or never true (NT) 1. Atoms of one element change into atoms of another element during chemical reactions. 2. Atoms combine in one-to-one ratios to form compounds. 3. Atoms of one element are different from atoms of other elements. 4. According to Dalton s atomic theory, atoms are composed of protons, electrons and neutrons. 5. Atoms of elements are electrically neutral. 6. The mass of an electron is equal to the mass of a neutron. 7. The charge on all protons is the same. 8. The atomic number of an element is the sum of the protons and electrons in an atom of that element. 9. An atom of nitrogen has 7 protons and 7 neutrons. 10. Relative atomic masses are expressed in amu's. 11. The number of neutrons in the nucleus can be calculated by subtracting the atomic number from the mass number. 12. In his periodic table, Mendeleev arranged the element in ascending order of atomic number. 13. The representative elements are the Group A elements. 14. The transition metals and inner transition metals are the Group B elements. 15. The element in Group 4A, period 3 is gallium. Match each description in Column B with the correct term in Column A Column A Column B 1. atom a. the group 7A elements 2. Dalton s atomic theory b. horizontal rows of the periodic table c. Group A elements 3. Democritius d. arrangement of elements according to 4. electrons similarities in their properties e. a portion of the B Group elements 5. protons f. Group 1A elements 6. neutrons g. Group 0 elements or group 8A 7. nucleus h. vertical column on the periodic table 8. atomic number i. represents the number of protons in an atom 9. mass number j. 1/12 of the mass of the carbon 12 atom 10. isotopes k. total number of protons and neutrons in an atom 11. atomic mass unit (amu) l. weighted average mass of the atoms in a 12. atomic mass naturally occurring sample of an element 13. periodic table m. atoms that have the same number of protons but different numbers of neutrons 14. periods n. positively charged subatomic particles 15. group o. subatomic particles with no charge 16. representative elements p. negatively charged subatomic particles 17. alkali metals q. the central positively charged core of the atom 18. transition metals r. teacher in ancient Greece 19. halogens s. theory to explain the reactive behavior of elements 20. noble gases t. smallest particle of an element that retains the properties of that element Solve the following problems:

2 1. Given the relative abundance of the following naturally occurring isotopes of oxygen, calculate the average atomic mass of oxygen: Oxygen % Oxygen % Oxygen % 2. A sample of chlorine contains 2 isotopes Cl-35 mass and Cl-37 mass Calculate the weighted average atomic mass if the relative abundance is 75.8% Cl-35 and 24.2% Cl What is the atomic mass of silicon if 92.21% of its atoms have mass amu, 4.70% have mass amu, and 3.09% have mass amu? 4. Calculate the numbers of each subatomic particle for the isotopes provided: 81 a. Se b. Cs 2 55 c. Zn-32 d. Sn 4+ e. Al 5. Name the following elements and classify them as metal, nonmetal, transition metal or metalloid. a. halogen in period 5 b. Group 3B period 5 c. Alkaline earth metal in period 3 d. Group 3A and period 2 Answers: amu ; amu; amu

3 Honors Chemistry: Chapter 5- Problem Set All answers and work on a separate sheet of paper! Definition Matching: Match the terms in Column A with the Definitions in Column B. Column A Column B 1. quantum a. the most stable arrangement of electrons around 2. excited state the nucleus of an atom 3. atomic orbitals b. 1s 2 2s 2 2p 6 4. quantum mechanical model c. Electrons enter orbitals of lowest energy first 5. photons d. One electron per oribital before double up 6. de Broglie s equation e. An atomic orbital can only hold two electrons 7. visible light f. region of space around the nucleus which has a 8. ground state high probability of containing an electron 9. wavelength g. the amount of energy required to move an electron 10. neon from its present energy level to the next level 11. Hund s rule h. modern description of electron behavior 12. Pauli exclusion principle i. light quanta 13. Aufbau Principle j. predicts that all matter exhibits wavelike motions 14. electron configuration k. the distance between two consecutive wave crests l. the lowest energy level for a given electron m. when the electrons are not in their lowest energy states n. example of electromagnetic radiation Answer the following questions: 1. How many orbitals are in each of the following sublevels? a. 4p b. 3d c. 4f d. 2s 2. Identify the elements described below: a. contains a full third energy level b. contains only 1 electron in the 4p sublevel c. contains only 1 electron in the 5s sublevel d. contains 5 electrons in the 4s and 4p sublevel e. contains 3 electrons in the 4d sublevel 3. For each of the following elements draw orbital diagrams. a. C b.s c. K d.ar 4. For each of the following elements, write electron configurations. a. Fe b. Lead c. Uranium d. Zinc e. Tungsten 5. How does quantum theory explain the photoelectric effect 6. Write an electron configuration for an atom of calcium in the excited state 7. Write electron configurations for each of the following ions: a. O 2- b. Al 3+ c. Cu 2+ d. P 3- Solve the following problems: 1. What is the frequency of radiation whose wavelength is 2.40 x 10-3 m? 2. How much energy is associated with a green wavelength of visible light that has a wavelength of 4.86 nm?

4 3. What is the frequency of a photon having a wavelength 662 nm? 4. The frequency of a green photon is 6.26 x Hz. What is the wavelength? 5. Calculate the frequency of a wave that has a wavelength of 6.0 x 10-3 m. 6. Calculate the frequency of an x-ray having a wavelength of 2.5 x 10 4 nm. 7. Calculate the energy associated with a microwave having a frequency of 7.5 x s Calculate the energy of a photon having a wavelength of 6.6 x 10-3 m. 9. How much energy is associated with a photon in the ultraviolet region of the spectrum with a frequency of 6.6 x s -1? 10. How much energy is associated with a light that measures 3.50 in the spectroscope? This chart summarizes the quantum model of the hydrogen atom. For each energy change in the chart below, calculate quantities needed to complete the chart. Show your work! Use energy transition to determine if the energy is released or absorbed. Transition E (J) v (s -1 ) λ (m) Is energy Released or Absorbed n=6 to n= x n=3 to n= x n=6 to n= x 10-7 n=1 to n= x n=2 to n= x 10-7 How does the energy associated with transitions between higher energy levels compare to those that are between lower energy levels? Answers to PS 5: x Hz x J x Hz x 10-7 m x Hz x Hz x J x J x J x Chart: v λ a x x 10-6 b x x 10-6 c x x 10-7 d x x 10-7 e x x 10-7

5 Honors Chemistry: Problem Set Chapter 6 All answers and work on a separate sheet of paper! Match the terms in Column A with the definitions in Column B 1. ionization energy a. half the distance between the nuclei of two atoms 2. electronegativity b. when the elements are arranged in order of increasing 3. atomic radius atomic number, there is a periodic pattern in their 4. cations physical and chemical properties. 5. periodic law c. positively charged ion d. tendency for the atoms of an element to attract electrons when they are chemically combined with another element 1. period a. an element in which the outermost s and p sublevels are 2. inner transition metal filled 3. representative elements b. a horizontal row on the periodic table 4. transition metal c. an element whose outermost s sublevel and nearby d 5. noble gas contain electrons 6. group d. an element whose outermost s and nearby f sublevel contain electrons. e. a vertical column on the periodic table f. an element whose outermost s or p sublevels are only partially filled Elements Li, Be, B, C Be, Mg, Ca, Sr Sn, As S, F Ga, Ge, As, Se Se, Br, Te, I Ca, Sr, Se, Br W, Pb, Sb, P Ni, Pt, Kr, I Most Metallic Largest Radius Highest Ionization Energy Lowest Electronegativity Highest Electron Affinity Fr, Ba, C, N Explain why Ba has a lower ionization energy then Mg. Why does atomic size decrease proceeding left to right across a period? 1. Consider the following elements: Ca, H, Co, Al, Si, S, Cl a. How many would be conductive? b. How many would likely be liquid or gas? c. How many will likely form colored compounds? d. How many are metalloids? 2. Write the symbol for the element that is described below. a. Period 3 alkali metal. b. Outer electron configuration is 4s 2 4p 4. c. Has 7 valence electrons in the 5s and 5p. d. Metalloid in period 3. e. Smallest noble gas. f. Largest alkali metal. g. Most electronegative period 2 element. h. Most reactive halogen. i. Most reactive alkali metal.

6 Honors Chemistry: Review Unit 2 All answers and work on a separate sheet of paper! 1. Complete the table for the following elements: Element Name A-Z Format Mass Format # of Protons # of electrons # of Neutrons Atomic # Mass # Mn 12 Br As-76 Actinium How many neutrons are in each atom? a. 23 Na b. 81 Br c. 19 F Element X has two isotopes: X-100 and X-104. If the atomic mass of X is amu, which isotope is more abundant and why? 4. Identify each element as a metal, metalloid, or nonmetal. a. fluorine b. germanium c. zinc d. phosphorus e. lithium f. hydrogen 5. Name two elements that have properties similar to potassium. 6. How many sublevels are in the following principal energy levels? a. n = 1 c. n=3 e. n=5 b. n=2 d. n=4 f. n=6 7. How many orbitals are in the following sublevels? a. 1s b. 5s c. 4d d. 4f e. 7s f. 3p g. 5 th energy level h. 6d 8. Write an orbital diagram for the following elements. a. Magnesium b. Oxygen 9. Write a complete electron configuration for each of the following elements. a. hydrogen: b. vanadium c. seaborgium d. barium ion (Ba 2+ ) e. bromide (Br - ) f. silver g. krypton h. arsenic i. radon j. tungsten k. gold 10. Arrange the following types of electromagnetic radiation in order of increasing energy. a. infared c. visible light e. microwaves b. cosmic rays d. radio waves f. ultraviolet rays

7 11. Subatomic particle Who discovered What was the experiment What observations were made Proton Neutron Electron 12. Describe the 4 aspects of Dalton s model of the atom. 13. Describe Rutherford s atom. How was the deflection of alpha particles explained by his model? Solve: 14. The two most abundant isotopes of carbon are carbon-12 ( mass amu) and carbon 13 (mass amu). Their relative abundances are 98.9% and 1.10% respectively. Calculate the atomic mass of carbon. 15. What is the wavelength of the radiation whose frequency is 5.00 xo Hz? 16. An inexpensive laser that is available to the public emits light that has a wavelength of 670 nm. What are the color and frequency of the radiation? 17. What is the energy of a photon whose frequency is 2.22 x Hz? 18. What is the wavelength of a photon whose energy is 6.00 x J? 19. Suppose that you favorite AM radio station broadcasts at a frequency of 1600 KHz. What is the wavelength in meters of the radiation from the station? 20. Which family of elements is characterized by and s 2 p 3 configuration? 21. Consider the elements: Br, S, V, Rb, Ag, Sb, H, Al a. How many would be lusterous? b. How many are metalloids? c. How many would have colored compounds? d. How many would be solid at room temperature? e. How many would be ductile? 22. Name the elements that are described below: a. one that has 5 outer electrons on the third period b. one with 4s 2 4p 5 electron configuration c. the 4 th period, group 6A element d. outer electron configuration 2s 2 2p 4 e. 4s 2 f. 3d 10 4s Why would you expect sodium and lithium to have similar chemical and physical properties? 24. Explain why Mg is smaller than atoms of sodium and calcium. 25. Arrange the following elements in order of decreasing ionization energy: a. Cs, Li, K b. Cl, Si, P,Ar c. Ca, Ba, Be, Sr 26. Which element in each pair has the higher electronegativity? a. Na, Mg b. Rb, I c. Cl, Br