Double Replacement Reaction

SHOW ALL WORK - includes equation, substitution with units, and answer with correct sig figs and units 1. A metal has a volume of 42.5 mL and a mass of 305.6 grams. Identify the metal. D = M/V = 305.6 g / 42.5 mL = 7.19 g/mL 2. How much heat is required to melt 450 grams of ice? q = m * Hf = 450 g * 334 J/g = 150300 J 3. A sample of an element contains 78.2% Sr-88 and 21.8% Sr-87. What is the average atomic mass for this element? (78.2/100 * 88) + (21.8/100 * 87) = 68.816 + 18.966 = 87.782 amu 4. How much heat is released when a 150 gram sample of water is cooled from 75.0 C down to 37.0 C? q = m * C * ΔT = 150 g * 4.18 J/g°C * (38°C) = 23826 J 5. What is 45.6 C in Kelvin? 318.6 K If this temperature increases by 15 C, how much will the Kelvin temperature increase? Both change 15 degrees 6. A student calculates the density for Aluminum to be 2.58 g/mL. What is his percent error? %error = (|measured - actual| / actual) x 100 = |2.58 g/mL - 2.698 g/mL| / 2.698 g/mL x 100 = 4.37% 7. Label the following heating curve with phases, phase changes, areas of changing KE and PE, and areas of constant KE and PE. heating curve with labels for solid, liquid, gas phases, melting point (MP), boiling point (BP), and arrows indicating changes in kinetic energy (KE) and potential energy (PE) 8. How much heat is released when 25.0 grams of steam are condensed into a liquid at 100°C? q = m * Hv = 25.0 g * 2260 J/g = 565,000 J 9. Determine the number of protons, electrons, and neutrons in the following: a. Ga p = 31 e = 31 n = 39 b. Cl⁻ p = 17 e = 18 n = 18 c. Zr p = 40 e = 40 n = 50 d. Al³⁺ p = 13 e = 10 n = 14 10. Write the electron configuration for the above atoms and ions: a. 2-8-18-3 b. 2-8-8 c. 2-8-18-10-2 d. 2-8 11. Draw the Lewis electron-dot diagram for the above atoms and ions: a. Ga: [Ga]• b. Cl⁻: [Cl]⁻ c. Zr: [Zr] d. Al³⁺: [Al]³⁺ 12. How does an atom of Ba become a Ba²⁺ ion? loses 2e⁻ 13. Draw particle diagrams for the following: a. Al - an element: [Diagram of Al atoms] b. O₂ - an element: [Diagram of O₂ molecules] c. H₂O - a compound: [Diagram of H₂O molecules] d. air - a mixture of elements: [Diagram of various gas molecules mixed] e. NaCl(aq) - a mixture of compounds: [Diagram of Na⁺ and Cl⁻ ions in water] 1. Which equation represents a double replacement reaction? A) 2Na + 2H₂O → 2NaOH + H₂ B) LiOH + HCl → LiCl + H₂O C) CH₄ + 2O₂ → CO₂ + 2H₂O D) CaCO₃ → CaO + CO₂ 2. In comparison to an atom of F in the ground state, an atom of Cl in the ground state has A) three more valence electrons B) three more neutrons C) three fewer valence electrons D) three fewer neutrons 3. Conductivity in a metal results from the metal atoms having A) highly mobile protons in the nucleus B) highly mobile electrons in the valence shell C) high ionization energy D) high electronegativity 4. Which type of bond is formed when electrons are transferred from one atom to another? A) covalent B) metallic C) ionic D) hydrogen 5. What is the empirical formula for the compound C₆H₁₂O₆? A) C₆H₁₂O₆ B) C₂H₄O₂ C) C₃H₆O₃ D) CH₂O 6. The elements in the Periodic Table are arranged in order of increasing A) neutron number B) atomic radius C) atomic number D) mass number 7. The temperature of 50. grams of water was raised to 50°C by the addition of 4180 joules of heat energy. What was the initial temperature of the water? A) 10°C B) 20°C C) 30°C D) 60°C 8. Expressed to the correct number of significant figures, what is the sum of (3.04 g + 4.134 g + 6.1 g)? A) 13.27 g B) 13.3 g C) 13.274 g D) 13 g 9. Which particles are found in the nucleus of an atom? A) protons and neutrons B) protons and electrons C) neutrons only D) electrons only 10. Covalent bonds are formed when electrons are A) captured by the nucleus B) mobile within a metal C) transferred from one atom to another D) shared between two atoms 11. How many electrons are contained in an Au³⁺ ion? A) 79 B) 197 C) 82 D) 76 12. Element X is a solid that is brittle, lacks luster, and has six valence electrons. In which group on the Periodic Table would element X be found? 1   A) 1 B) 2 C) 15 D) 16 13. What is the total number of valence electrons in an atom of sulfur in the ground state? A) 6 B) 8 C) 3 D) 4 14. Which electron configuration represents the electrons of an atom in an excited state? A) 2-7-2 B) 2-4 C) 2-8-2 D) 2-6 15. What occurs when an atom of chlorine forms a chloride ion? A) The chlorine atom loses an electron, and its radius becomes larger. B) The chlorine atom gains an electron, and its radius becomes smaller. C) The chlorine atom loses an electron, and its radius becomes smaller. D) The chlorine atom gains an electron, and its radius becomes larger.