2. What is the energy of a single photon of blue light with a wavelength of 4.50 x 10-7 m?

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1 2013 Chemistry Fall Exam Review Concepts to review/explain: 1. Using the periodic table, what is the electron configuration for Sulfur, Calcium and Copper? 2. What is the energy of a single photon of blue light with a wavelength of 4.50 x 10-7 m? 3. Compare solids, liquids, and gases on the basis of compressibility, structure, shape, volume, and motion of the particles. 4. Explain the properties of chemical families on the Periodic Table, including: (Why does each of these families have the unique properties they have?) alkali metals, alkaline earth metals, halogens, noble gases, transition metals 5. Identify and explain periodic trends including atomic radii, ionic radii, electronegativity, ionization energy 6. Describe characteristics of alpha, beta, and gamma radiation. 7. Compare and contrast fission and fusion reactions. 8. What important discoveries led to our current understanding of the structure of the atom? 9. How did the periodic table of elements evolve over time? 10. What type of nuclear radiation is emitted when Radium-222 decays to produce Radon-218? 11. What is the electron dot formula for? (Ca; As; ammonia, NH 3; magnesium chloride, MgCl 2 ) 12. What is the difference between physical and chemical changes/properties? 13. Contrast extensive and intensive properties. 14. How can you determine whether a mixture is a homogeneous or heterogeneous mixture?

2 Naturally Occurring Isotopes of Unknown Element Atomic Mass (amu) Percent Natural Abundance (%) Calculate the average atomic mass of the unknown element to the nearest hundredth of an atomic mass unit. 16. How is the nature of metallic bonding different from other types of bonding and how does this explain the properties of metals? 17. Draw a diagram to represent the electromagnetic spectrum. Draw and label how wavelength, frequency and energy change along the electromagnetic spectrum. 18. Write the names of the following substances: LiBr N 2 O 5 CuO SF 6 CoBr 2 H 2 S NaNO 3 Mg(NO 3 ) 2 Ca(MnO 4 ) 2 P 4 O Write the formulas for the following substances: lithium dichromate ammonium nitrogen barium sulfite chromium (VI) nitride copper (II) phosphide beryllium carbide dialuminium hexabromide arsenic pentaflouride 20. The equation below represents a nuclear reaction. What is the mass number of the missing particle in this reaction? Record your answer

3 Sample Questions for Review: 2013 Chemistry Fall Exam Review CONTINUED Densities of Substances Brass 8.40 g/cm 3 Concrete 2.30 g/cm 3 Silver 10.5 g/cm 3 Lead 11.3 g/cm 3 1. The mass of a 52.2 cm 3 sample of a substance is 120 g. Calculate the density and use it to identify the substance and classify it as a pure substance or a mixture. A B C D 2. The model for predicting the shape of molecules that is based on the repulsion of electron pairs is called VSEPR theory. Based upon VSEPR, what is the molecular structure of _?_ (boron trifluoride, BF 3, carbon tetrachloride, CCl 4, sulfur fluoride, SF 2, or phosphorus trichloride, PCl 3) A Trigonal pyramidal B C D homogeneous mixture heterogeneous mixture element compound Tetrahedral Bent Trigonal planar 3. Barium chloride is often used to make a green color in fireworks. The wavelength of light emitted by lithium carbonate is 5.89 x 10-7 m. What is the frequency of this light? A 1.96 x s -1 B 196 s -1 C 5.09 x s -1 D 5.09 x s An atom of carbon-14 decays producing a beta particle. What isotope is produced along with the beta particle? A B C D 13 C 6 14 N 7 18 O 8 7 Be 4

4 5. Elements in a group of the periodic table are described below. These elements most likely belong to which group? A Alkali metals B Alkaline earth metals C Halogens D Noble gases 6. A detail from a label on a bottle of a water-softening agent is shown below. Which inference about the contents of the bottle can best be drawn? A They consist of barium chloride anhydrous. B They consist of barium chloride dihydrate. C They consist of barium chloride hexahydrate. D They consist of barium chloride heptahydrate. 7. Some students used a variety of procedures to investigate four liquid samples. The students recorded the following information. When Sample W was cooled, solid particles settled out of the liquid. The mass and volume of Sample X were measured, and the density of Sample X was calculated to be 1.6 g/ml. Sample Y was heated, and the temperature was recorded. All the liquid boiled away at the same temperature and left no residue in the container. When a dilute acid was added to Sample Z, gas bubbles formed and rapidly rose to the surface of the liquid. Based on these observations, which sample was clearly identifiable as a pure substance? A Sample W B Sample X C Sample Y D Sample Z 8. In a famous experiment conducted by Ernest Rutherford, positively charged alpha particles were scattered by a thin gold foil. Which of the following is a conclusion that resulted from this experiment? F The nucleus is negatively charged. G The atom is a dense solid and is indivisible. H The mass is conserved when atoms react chemically. J The nucleus is very small and the atom is mostly empty space.

5 9. The following table lists some properties of copper and sulfur. Samples of copper metal and sulfur powder are placed in the same test tube and heated over a Bunsen burner. The resulting substance has the following properties. Does not conduct electricity Has a density of 5.6 g/cm3 Has a metallic luster Is a black brittle crystalline solid This black substance is classified as A a heterogeneous mixture B an element C a compound D a homogeneous mixture 10. Sodium, mercury, argon, and neon are used in the production of lamps. There are fewer safety guidelines regarding the handling of neon and argon than for mercury and sodium. Which of the following best describes the elements within the group of the periodic table that contains neon and argon gas? F Gaseous at room temperature and highly reactive with metals G Solid at room temperature and mildly reactive with strong acids H Gaseous at room temperature and mostly unreactive with metals J Solid at room temperature and mostly unreactive with strong acids 11. A material safety data sheet (MSDS) for a chemical is shown below. Which of these is the IUPAC name for H 3 PO 4 (aq)? F Trihydrogen phosphite G Phosphoric acid H Phosphorous hydroxide J Phosphorous acid

6 12. The diagram below shows part of Dmitri Mendeleev s original periodic table, with symbols of known elements and their atomic masses. Mendeleev s arrangement of elements is different than that of the modern periodic table. Based on Mendeleev s arrangement, which elements should be placed in the shaded boxes labeled X and Z respectively? A Indium (In), because it has a slightly higher atomic mass than aluminum (Al), and tin (Sn), because it has a slightly higher atomic mass than silicon (Si) B Cadmium (Cd), because it has chemical properties similar to those of zinc (Zn), and mercury (Hg), because it has chemical properties similar to those of arsenic (As) C Antimony (Sb), because it has a slightly higher atomic mass than zinc (Zn), and bismuth (Bi), because it also has a higher atomic mass than zinc (Zn) D Gallium (Ga), because it has chemical properties similar to those of aluminum (Al), and germanium (Ge), because it has chemical properties similar to those of silicon (Si) 13. A scientist filters a sample of river water. The data from this process are listed below. These data support which of the following descriptions of the sample? A It is a pure substance because solid particles cannot pass through the filter paper. B It is a pure substance because the river water is composed only of free elements. C It is a mixture because dissolved ions in the water pass through the filter paper. D It is a mixture because solid particles are separated from the river water. 14. Chemists can identify the composition of some unknown salts by conducting a flame test. When potassium salts are heated in a flame, a purple color is observed. This is due to the movement of electrons between energy levels. What is the electron configuration of a potassium atom at ground state? A 1s 2 2s 2 2p 6 3s 2 3p 6 4d 1 B 1s 2 2s 2 2p 6 3s 2 3p 6 3d 1 C 1s 2 2s 2 2d 6 3s 2 3d 6 4s 1 D 1s 2 2s 2 2p 6 3s 2 3p 6 4s X-ray crystallography is a technique that allows scientists to determine the ionic and atomic radii of elements. Which of these statements correctly describes a trend in ionic or atomic radii in the periodic table? A The ionic radius decreases from top to bottom in a group. B The atomic radius increases from left to right across a period. C The ionic radius remains constant from right to left across a period. D The atomic radius increases from top to bottom in a group.