* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Name: 1) At 1 atmosphere and 298 K, 1 mole of H O(l) molecules
History of chemistry wikipedia , lookup
History of molecular theory wikipedia , lookup
X-ray fluorescence wikipedia , lookup
Diamond anvil cell wikipedia , lookup
Metastable inner-shell molecular state wikipedia , lookup
Water splitting wikipedia , lookup
Electrochemistry wikipedia , lookup
Acid dissociation constant wikipedia , lookup
Artificial photosynthesis wikipedia , lookup
Chemistry: A Volatile History wikipedia , lookup
Electron configuration wikipedia , lookup
Hypervalent molecule wikipedia , lookup
Crystallization wikipedia , lookup
Photoredox catalysis wikipedia , lookup
Chemical thermodynamics wikipedia , lookup
Vapor–liquid equilibrium wikipedia , lookup
Chemical reaction wikipedia , lookup
Strychnine total synthesis wikipedia , lookup
Biochemistry wikipedia , lookup
Marcus theory wikipedia , lookup
Click chemistry wikipedia , lookup
Stoichiometry wikipedia , lookup
George S. Hammond wikipedia , lookup
Hydroformylation wikipedia , lookup
Acid–base reaction wikipedia , lookup
Physical organic chemistry wikipedia , lookup
Lewis acid catalysis wikipedia , lookup
Rutherford backscattering spectrometry wikipedia , lookup
Metalloprotein wikipedia , lookup
Atomic theory wikipedia , lookup
Chemical equilibrium wikipedia , lookup
Enzyme catalysis wikipedia , lookup
Electrolysis of water wikipedia , lookup
Bioorthogonal chemistry wikipedia , lookup
6569 - 1 - Page 1 Name: ____________________________________________ 1) At 1 atmosphere and 298 K, 1 mole of H2 O(l) molecules and 2) 1 mole of C2 H5 OH(l) molecules both have the same A) B) C) D) mass density average kinetic energy vapor pressure Two samples of gold that have different temperatures are placed in contact with one another. Heat will flow spontaneously from a sample of gold at 60DC to a sample of gold that has a temperature of A) 50DC B) 60DC 3) Which kelvin temperature is equivalent to -24DC? A) 273 K B) 226 K 4) C) 70DC D) 80DC C) 297 K D) 249 K At equilibrium, nitrogen, hydrogen, and ammonia gases form a mixture in a sealed container. The data table below gives some characteristics of these substances. Describe how to separate ammonia from hydrogen and nitrogen. 5) In which equation does the term "heat" represent heat of fusion? 9) A) NaOH(aq) + HCl(aq) ‚ NaCl(aq) + H2 O(l) + heat B) H2 O(l) + heat ‚ H2 O(g) C) NaCl(s) + heat ‚ NaCl(l) D) H2 O(l) + HCl(g) ‚ H3 O+(aq) + Cl-(aq) + heat 6) A) water B) propanone 10) Given the particle diagram: 7) Which grouping of the three phases of bromine is listed in order from left to right for increasing distance between bromine molecules? A) solid, liquid, gas B) liquid, solid, gas 8) C) Xe D) Rn C) solid, gas, liquid D) gas, liquid, solid As the pressure on the surface of a liquid decreases, the temperature at which the liquid will boil A) remains the same B) decreases C) increases C) ethanol D) ethanoic acid Using your knowledge of chemistry and the information in the Vapor Pressure of Four Liquids chemistry reference table, which statement concerning propanone and water at 50DC is true? A) Propanone has a lower vapor pressure and weaker intermolecular forces than water. B) Propanone has a lower vapor pressure and stronger intermolecular forces than water. C) Propanone has a higher vapor pressure and weaker intermolecular forces than water. D) Propanone has a higher vapor pressure and stronger intermolecular forces than water. At 101.3 kPa and 298 K, which element could this diagram represent? A) Kr B) Ag Based on the Vapor Pressure of Four Liquids chemistry reference table, which substance has the weakest intermolecular forces? 11) Which phase change results in the release of energy? A) H2 O(g) ‚ H2 O(l) B) H2 O(s) ‚ H2 O(l) C) H2 O(l) ‚ H2 O(g) D) H2 O(s) ‚ H2 O(g) 6569 - 1 - Page 2 12) The graph below represents the uniform heating of a substance, starting below its melting point, when the substance is solid. 15) Under which conditions of temperature and pressure would helium behave most like an ideal gas? A) 750 K and 600 kPa B) 50 K and 600 kPa 16) The temperature of a 2.0-liter sample of helium gas at STP is increased to 27DC and the pressure is decreased to 80. kPa. What is the new volume of the helium sample? A) 2.0 L B) 1.4 L 17) 13) 14) C) 50 K and 20 kPa D) 750 K and 20 kPa C) 2.8 L D) 4.0 L At STP, 4 liters of O2 contains the same total number of molecules as A) 4 L of CO2 C) 2 L of Cl2 B) 1 L of NH3 D) 8 L of He Which line segments represent an increase in average kinetic energy? Questions 18 and 19 refer to the following: A) DE and EF B) AB and BC The diagram below shows a piston confining a gas in a cylinder. C) AB and CD D) BC and DE Explain, in terms of molecular energy, why the vapor pressure of propanone increases when its temperature increases. 18) Using the set of axes below, sketch the general relationship between the pressure and the volume of an ideal gas at constant temperature. 19) The gas volume in the cylinder is 6.2 milliliters and its pressure is 1.4 atmospheres. The piston is then pushed in until the gas volume is 3.1 milliliters while the temperature remains constant. Calculate the pressure, in atmospheres, after the change in volume. [Show all work.] Given the graph below that represents the uniform cooling of a sample of lauric acid starting as a liquid above freezing point. (a) Which line segment represents a phase change, only? (b) What is the melting point of lauric acid? (c) At which point do the particles of lauric acid have the highest average kinetic energy? (d) Name the phase change that takes place during this 10-minute cooling time. 6569 - 1 - Page 3 Questions 20 and 21 refer to the following: 26) Which electron transition represents a gain of energy? A) B) C) D) Cylinder A contains 22.0 grams of CO2 (g) and cylinder B contains N2 (g). The volumes, pressures, and temperatures of the two gases are indicated under each cylinder. 27) What determines the order of placement of the elements on the modern Periodic Table? A) B) C) D) 28) from 3rd to 2nd shell from 2nd to 3rd shell from 3rd to 1st shell from 2nd to 1st shell the number of neutrons, only the number of neutrons and protons atomic number atomic mass Which set of symbols represents atoms with valence electrons in the same electron shell? A) Ba, Br, Bi B) Mn, Hg, Cu 29) 20) Explain why the number of molecules of N2 (g) in cylinder B is the same as the number of molecules of CO2 (g) in A) 13 30) The temperature of the CO2 (g) is increased to 450. K and the volume of cylinder A remains constant. Show a correct numerical setup for calculating the new pressure of the CO2 (g) in cylinder A. 22) attached to one unit of MgSO4 .] 23) 24) B) 4 D) 7 31) A) a hard sphere with negative particles uniformly embedded B) a hard sphere with positive particles uniformly embedded C) a positive nucleus surrounded by a hard negative shell D) a positive nucleus surrounded by a cloud of negative charges A) decreases B) increases 32) 33) C) B) D) 34) filled energy levels mobile electrons high ionization energies high electronegativities Which change occurs when a barium atom loses two electrons? A) B) C) D) Which Lewis electron-dot diagram represents a boron atom in the ground state? C) remains the same The high electrical conductivity of metals is primarily due to A) B) C) D) C) an ion D) the nucleus A) D) 14 When an atom of phosphorus becomes a phosphide ion (P3-), the radius The region that is the most probable location of an electron in an atom is C) 2 As the elements in Period 2 of the Periodic Table are considered in succession from left to right, there is a decrease in atomic radius with increasing atomic number. This may best be explained by the fact that the Which of these phrases best describes an atom? A) the excited state B) an orbital 25) C) 5 B) 1 A) number of protons increases, and the number of shells of electrons increases B) number of protons increases, and the number of shells of electrons remains the same C) number of protons decreases, and the number of shells of electrons increases D) number of protons decreases, and the number of shells of electrons remains the same What is the total number of oxygen atoms in the formula MgSO4 d7H2 O? [The d represents seven units of H2 O A) 11 An unknown element X can form a compound with the formula XBr3 . In which group on the Periodic Table would element X be found? cylinder A. 21) C) Sr, Sn, I D) O, S, Te It becomes It becomes It becomes It becomes a negative ion and its radius increases. a negative ion and its radius decreases. a positive ion and its radius decreases. a positive ion and its radius increases. At standard pressure, which element has a melting point higher than standard temperature? A) Br2 C) F2 B) Hg D) Fe 6569 - 1 - Page 4 35) Which trends are observed when the elements in Period 3 on the Periodic Table are considered in order of increasing atomic number? A) The atomic radius decreases, and the first ionization energy generally increases. B) The atomic radius increases, and the first ionization energy generally increases. C) The atomic radius decreases, and the first ionization energy generally decreases. D) The atomic radius increases, and the first ionization energy generally decreases. 36) Based on the Properties of Selected Elements chemistry reference table, which of the following atoms requires the least energy for the removal of the most loosely bound electron? A) Br B) Sr 37) The table below shows the electronegativity of selected elements of Period 2 of the Periodic Table. 41) C) Be D) Sn (a) On the grid below, set up a scale for electronegativity on the y-axis. (b) Plot the data by drawing a best-fit line. Which list consists of elements that have the most similar chemical properties? A) K, Al, and Ni B) K, Ca, and Ga 38) Questions 41 and 42 refer to the following: C) Mg, Al, and Si D) Mg, Ca, and Ba At 298 K, oxygen (O2 ) and ozone (O3 ) have different properties because their A) B) C) D) 39) atoms have different atomic numbers atoms have different atomic masses molecules have different average kinetic energies molecules have different molecular structures Which statement correctly describes diamond and graphite, which are different forms of solid carbon? A) They do not differ in their molecular structure or properties. B) They differ in their properties, only. C) They differ in their molecular structure and properties. D) They differ in their molecular structure, only. 40) Potassium ions are essential to human health. The (c) Using the graph, predict the electronegativity of nitrogen. 42) For the elements in the table, state the trend in electronegativity in terms of atomic number. 43) As two chlorine atoms combine to form a molecule, energy is movement of dissolved potassium ions, K+(aq), in and out of a nerve cell allows that cell to transmit an electrical impulse. What property of potassium ions allows them to transmit an electrical impulse in the situation described? A) released B) destroyed 44) Which of the following elements has the least attraction for electrons in a chemical bond? A) chlorine B) fluorine 45) C) created D) absorbed C) nitrogen D) oxygen Which of the following solids has the highest melting point? A) SO2 (s) C) H2 O(s) B) CO2 (s) D) Na2 O(s) 6569 - 1 - Page 5 46) What is the correct Lewis electron-dot structure for the compound magnesium fluoride? 51) A) 52) B) Which formula represents a nonpolar molecule? A) HCl C) H2 O B) CF4 D) NH3 Which Lewis electron-dot diagram is correct for CO2 ? A) C) B) D) C) D) 53) 47) 48) intermolecular forces Which compound contains both ionic and covalent bonds? A) CaCO3 C) PCl3 B) CH2 O D) MgF2 A solid substance was tested in the laboratory. The test results are listed below. Molecules in a sample of NH3 (l) are held closely together by A) B) C) D) 54) caused by different numbers of neutrons existing between ions caused by unequal charge distribution existing between electrons The table below shows the normal boiling point of four compounds. d dissolves in water d is an electrolyte d melts at a high temperature Based on these results, the solid substance could be A) C B) CuBr2 49) 50) C) Cu D) C6 H12 O6 Which molecule contains a triple covalent bond? A) N2 C) H2 Which compound has the strongest intermolecular forces? B) Cl2 D) O2 A) HCl(l) B) CH3 F(l) Which substance is correctly paired with its type of bonding? A) NaBr ‡‡ nonpolar covalent B) HCl ‡‡ nonpolar covalent C) Br2 ‡‡ polar covalent D) NH3 ‡‡ polar covalent C) HF(l) D) CH3 Cl(l) 6569 - 1 - Page 6 55) In the boxes below, draw a correct Lewis electron-dot structure for: (a) an atom of hydrogen (b) an atom of nitrogen (c) a molecule of ammonia (NH3 ) Questions 56 and 57 refer to the following: 62) A) The boiling point of the solution increases, and the freezing point of the solution increases. B) The boiling point of the solution increases, and the freezing point of the solution decreases. C) The boiling point of the solution decreases, and the freezing point of the solution decreases. D) The boiling point of the solution decreases, and the freezing point of the solution increases. Naphthalene, a nonpolar substance that sublimes at room temperature, can be used to protect wool clothing from being eaten by moths. 56) Explain, in terms of intermolecular forces, why naphthalene sublimes. 57) Explain why naphthalene is not expected to dissolve in water. 58) The solubility of KClO3 (s) in water increases as the A) B) C) D) 59) temperature of the solution increases temperature of the solution decreases pressure on the solution increases pressure on the solution decreases 60) C) sodium nitrate D) sugar 64) According to Solubility Curves chemistry reference table, which solution is saturated at 30DC? C) 30 grams of NaCl in 200 grams of water D) 12 grams of KClO3 in 200 grams of water 65) A student is instructed to make 0.250 liter of a 0.200 M aqueous solution of Ca(NO3 )2 . Show a correct numerical setup for calculating the total number of moles of Ca(NO3 )2 needed to make 0.250 liter of a C) 2 M D) 8 M C) 0.02 ppm D) 2 ppm C) 84 g D) 38 g A) 30 grams of NaCl in 100 grams of water B) 12 grams of KClO3 in 100 grams of water 0.200 M calcium nitrate solution. What is the concentration of a solution, in parts per million, if 0.02 gram of Na3 PO4 is dissolved in 1,000 grams of water? A) 20 ppm B) 0.2 ppm Based on the Solubility Curves chemistry reference table, what is the maximum number of grams of KCl(s) that will dissolve in 200 grams of water at 50DC to produce a saturated solution? A) 42 g B) 58 g What is the molarity of a solution of NaOH if 2 liters of the solution contains 4 moles of NaOH? A) 80 M B) 0.5 M 61) 63) At room temperature, the solubility of which solute in water would be most affected by a change in pressure? A) carbon dioxide B) methanol What occurs when NaCl(s) is added to water? 66) Sulfur dioxide, SO2 , is one of the gases that react with water to produce acid rain. According to the Solubility Curves chemistry reference table, describe how the solubility of sulfur dioxide in water is affected by an increase in water temperature. 6569 - 1 - Page 7 Questions 67 and 68 refer to the following: 71) A student uses 200 grams of water at a temperature of 60DC to prepare a saturated solution of potassium chloride, KCl. 67) The solution described is cooled to 10DC and the excess KCl precipitates (settles out). The resulting solution is saturated at 10DC. How many grams of KCl precipitated out of the original solution? (a) Describe the solubility of CO2 gas in water. (b) Explain your response to part (a) in terms of the molecular polarities of CO2 (g) and H2 O(l). 72) Given the balanced equation: 4Fe(s) + 3O2 (g) ‚ 2Fe2 O3 (s) + 1,640 kJ 68) According to the Solubility Curves chemistry reference table, how many grams of KCl must be used to create the saturated solution described? Which phrase best describes this reaction? A) B) C) D) Questions 69 through 71 refer to the following: FIZZIES - A SPLASH FROM THE PAST They're baaack... a splash from the past! Fizzies instant sparkling drink tablets, popular in the 1950's and 1960's, are now back on the market. What sets them apart from other powdered drinks is that they bubble and fizz when placed in water, forming an instant carbonated beverage. The fizz in Fizzies is caused by bubbles of carbon dioxide (CO2 ) gas that are released when the tablet is dropped into water. 73) When a spark is applied to a mixture of hydrogen and oxygen, the gases react explosively. Which potential energy diagram best represents the reaction? A) Careful observation reveals that these bubbles rise to the surface because CO2 gas is much less dense than water. However, not all of the CO2 gas rises to the surface; some of it dissolves in the water. The dissolved CO2 can react with water to form carbonic acid, H2 CO3 . B) H2 O(l) + CO2 (aq) ‰Š‹ H2 CO3 (aq) The pH of the Fizzies drink registers between 5 and 6, showing that the resulting solution is clearly acidic. Carbonic acid is found in other carbonated beverages as well. One of the ingredients on any soft drink label is carbonated water, which is another name for carbonic acid. However, in the production of soft drinks, the CO2 C) is pumped into the solution under high pressure at the bottling plant. ‡‡Brian Rohrig, Excerpted from "Fizzies ‡‡ A Splash from the Past," Chem Matters, February 1998 69) What is the only positive ion in an aqueous solution of carbonic acid? D) 70) CO2 is pumped into the soft drink solution under high pressure. Why is high pressure necessary? endothermic with DH = -1,640 kJ endothermic with DH = +1,640 kJ exothermic with DH = +1,640 kJ exothermic with DH = -1,640 kJ 6569 - 1 - Page 8 74) The potential energy diagram below represents a reaction. 75) Given the potential energy diagram for a chemical reaction: Which arrow represents the activation energy of the forward reaction? A) A B) B C) C D) D Which statement correctly describes the energy changes that occur in the forward reaction? A) The activation energy is 10. kJ and the reaction is exothermic. B) The activation energy is 50. kJ and the reaction is endothermic. C) The activation energy is 10. kJ and the reaction is endothermic. D) The activation energy is 50. kJ and the reaction is exothermic. 76) In each of the four beakers shown below, a 2.0-centimeter strip of magnesium ribbon reacts with 100 milliliters of HCl(aq) under the conditions shown. In which beaker will the reaction occur at the fastest rate? A) A 77) B) B Which statement best explains the role of a catalyst in a chemical reaction? A) A catalyst is added as an additional reactant and is consumed but not regenerated. B) A catalyst limits the amount of reactants used. C) A catalyst changes the kinds of products produced. D) A catalyst provides an alternate reaction pathway that requires less activation energy. C) C 78) A catalyst is added to a system at equilibrium. If the temperature remains constant, the activation energy of the forward reaction A) remains the same B) increases 79) D) D C) decreases Which sample has the lowest entropy? A) 1 mole of KNO3 (s) C) 1 mole of H2 O(l) B) 1 mole of H2 O(g) D) 1 mole of KNO3 (l) 6569 - 1 - Page 9 80) Systems in nature tend to undergo changes toward A) B) C) D) 81) 84) higher energy and higher entropy lower energy and lower entropy higher energy and lower entropy lower energy and higher entropy N2 O4 (g) ‰Š‹ 2NO2 (g) Which statement correctly describes this system? A) The concentrations of N2 O4 and NO2 are both increasing. B) The forward and reverse reaction rates are equal. C) The forward and reverse reaction rates are both increasing. D) The concentrations of N2 O4 and NO2 are equal. In the smelting of iron ore, Fe2 O3 is reduced in a blast furnace at high temperature by a reaction with carbon monoxide. Crushed limestone, CaCO3 , is also added to the mixture to remove impurities in the ore. The carbon monoxide is formed by the oxidation of carbon (coke), as shown in the following reaction: 2C + O2 ‚ 2CO + energy Given the equilibrium reaction at STP: 85) Liquid iron flows from the bottom of the blast furnace and is processed into different alloys of iron. A student adds solid KCl to water in a flask. The flask is sealed with a stopper and thoroughly shaken until no more solid KCl dissolves. Some solid KCl is still visible in the flask. The solution in the flask is A) B) C) D) Using the set of axes provided, sketch a potential energy diagram for the reaction of carbon and oxygen that produces the carbon monoxide in the situation described. 86) unsaturated and is not at equilibrium with the solid KCl saturated and is not at equilibrium with the solid KCl saturated and is at equilibrium with the solid KCl unsaturated and is at equilibrium with the solid KCl Given the reaction at equilibrium: A(g) + B(g) ‰Š‹ AB(g) + heat The concentration of A(g) can be increased by A) B) C) D) 87) 82) Which statement correctly describes a chemical reaction at equilibrium? A) The concentrations of the products and reactants are equal. B) The concentrations of the products and reactants are constant. C) The rate of the forward reaction is greater than the rate of the reverse reaction. D) The rate of the forward reaction is less than the rate of the reverse reaction. 83) 88) Which species can conduct an electric current? A) CH3 OH(aq) C) NaOH(s) B) HCl(aq) D) H2 O(s) The only positive ion found in an aqueous solution of sulfuric acid is the A) sulfate ion B) hydronium ion 89) 90) Which statement about a system at equilibrium is true? A) The forward reaction rate is less than the reverse reaction rate. B) The forward reaction rate stops and the reverse reaction rate continues. C) The forward reaction rate is greater than the reverse reaction rate. D) The forward reaction rate is equal to the reverse reaction rate. increasing the concentration of B(g) adding a catalyst lowering the temperature increasing the concentration of AB(g) Which substance is an Arrhenius acid? A) Mg(OH)2 (aq) C) HBr(aq) B) CH3 CHO D) LiF(aq) How are HNO3 (aq) and CH3 COOH(aq) similar? A) B) C) D) 91) 92) C) sulfite ion D) hydroxide ion They are Arrhenius They are Arrhenius They are Arrhenius They are Arrhenius acids and they turn blue litmus red. bases and they turn blue litmus red. acids and they turn red litmus blue. bases and they turn red litmus blue. One acid-base theory states that an acid is A) an electron donor C) an OH- donor B) a neutron donor D) an H+ donor Which of these pH numbers indicates the highest level of acidity? A) 12 B) 5 C) 10 D) 8 6569 - 1 - Page 10 93) 94) Which of these 1 M solutions will have the highest pH? A) NaCl C) CH3 OH B) HCl D) NaOH 100 times the original content 10 times the original content 0.01 of the original content 0.1 of the original content 96) C) H2 SO4 + Mg(OH)2 ‚ MgSO4 + 2H2 O D) Na2 CO3 + CaCl2 ‚ 2NaCl + CaCO3 98) Sulfuric acid, H2 SO4 (aq), can be used to neutralize barium hydroxide, Ba(OH)2 (aq). What is the formula for the salt produced by this neutralization? Which indicator is yellow in a solution with a pH of 9.8? A) methyl orange B) thymol blue Which equation represents a neutralization reaction? A) Ni(NO3 )2 + H2 S ‚ NiS + 2HNO3 B) NaCl + AgNO3 ‚ AgCl + NaNO3 When the pH of a solution changes from a pH of 5 to a pH of 3, the hydronium ion concentration is A) B) C) D) 95) 97) C) bromthymol blue D) bromcresol green A student was given four unknown solutions. Each solution was checked for conductivity and tested with phenolphthalein. The results are shown in the data table below. 99) A) BaSO3 C) BaS B) BaSO2 D) BaSO4 What is the molarity of an HCl solution if 20. milliliters of this acid is needed to neutralize 10. milliliters of a 0.50 M NaOH solution? A) 1.0 M B) 0.50 M C) 0.25 M D) 0.75 M Based on the data table, which unknown solution could be 0.1 M NaOH? A) A 100) B) B C) C D) D Four flasks each contain 100 milliliters of aqueous solutions of equal concentrations at 25DC and 1 atm. (a) Which solutions contain electrolytes? (b) Which solution has the lowest pH? (c) What causes some aqueous solutions to have a low pH? (d) Which solution is most likely to react with an Arrhenius acid to form a salt and water? (e) Which solution has the lowest freezing point? [Explain your answer.]