Naskah Ujian Tengah Semester Genap 2014/2015KIMIA SEKOLAH(take home)

Petunjuk.Kerjakan semua soal berikut.Jawaban menggunakan Bahasa Indonesia ditulis tangan dan dikumpulkan paling lambat hari Kamis, 2 April 2015 pukul 12.00.

Chapter 41. Applying Concepts Which is greater, the number of compounds or the number of elements? The number of atoms or the number of isotopes? Explain.(SKOR 5)2. Analyzing Information An element has three naturally occurring isotopes. What other information must you know in order to calculate the element's atomic mass?(SKOR 5)3. Applying Concepts If atoms are primarily composed of empty space, why can't you pass your hand through a solid object?(SKOR 5)

Chapter 54. Comparing and Contrasting Briefly discuss the difference between an orbit in Bohr's model of the atom and an orbital in the quantum mechanical viewof the atom.(SKOR 5)5. Applying Concepts Scientists use atomic emission spectra to determine the elements in materials ofunknown composition. Explain what makes thismethod possible.(SKOR 5)6. Writing in ChemistryIn order to make "neon" signs emit a variety of colors, manufacturers often fill the signs with gases other than neon. Research the use of gases in neon signs and specify the colors produced by the gases.(SKOR 5)

Chapter 67. Interpreting Data Given the following data about an atom's ionization energies, predict its valence electron configuration. Explain your reasoning, why 1st ionization < 2nd ionization < 3rd ionization.(SKOR 5)

Ionization Data

Lonizatitonlonization Energy (kJ/mol)

First734

Second1850

Third16432

8. Interpreting Data The melting points of the period 6 elements are plotted versus atomic number in the graph shown below. Determine the trends in melting point by analyzing the graph and the orbital configurations of the elements. Form a hypothesis that explains the trends. (Hint: In Chapter 5, you learned that half-filled sets of orbitals are more stable than other configurations of partially filled orbitals.)(SKOR 5)

Chapter 79. Applying Concepts Which element would be easiest to extract from its ore, gold or iron? Explain your choice.(SKOR 10)

Chapter 810. Concept Mapping Design a concept map to explain the physical properties of both ionic compounds and metallic solids.(SKOR 10)11. Predicting Predict which solid in each of the following will have the higher melting point. Explain your answer.(SKOR 10)a. NaCl or CsCl b. Ag or Cu c. Na2O or HgO

Chapter 912. Complete the concept map using the following terms: double bonds, one, phi, sigma, single bonds, three, triple bonds, two. Each term can be used more than once.(SKOR 5)

13. Predict the molecular shape and bond angle, andidentify the hybrid orbitals for each of the following. Drawing the Lewis structure may help you.(SKOR 10)a. SCl2b. NH2C1 c HOF d. BF314. For each of the following, predict the molecular shape.(SKOR 5)a. COS b. CF2Cl215. Identify the expected hybrid on the central atom foreach of the following. Drawing the Lewis structure may help you.(SKOR 10)a. XeF4 b. TeF4c. KrF2d. OF2