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1 According to the Bronsted—Lowry definition, which chemical species can function both as an acid and as a base? a Cl— b ( 4 )SO 2— c ( 4 )NH + d ( 3 )HCO — e H3O+ 2 In the reaction CN— + H2O  HCN +.

General Chemistry II Sample Test bank Page 1of 27 According to the Bronsted—Lowry definition, The weakest of the bases listed is which chemical species can function both as an acid and as a base? a Cl— b SO42— c NH4+ d HCO3— e H3O+ Acid HCl HSO4— SO42— H2S HS— HS— S2— a Cl— b CN— c HS— d S2— e SO42— In the reaction CN— + H2O  HCN + OH— which is an acid—base conjugate pair? a H2O and HCN b H2O and OH— c CN— and H2O d HCN and OH— Period First Second Third a b c d e The pH of a 0.03 M HCl solution is a 1.5 b 2.5 c 3.5 d 12.5 solution at Which is the strongest acid? a b c d HClO HClO2 HClO3 HClO4 Which salt reacts with water (hydrolyzes) to produce a basic solution? a b c d NaC2H3O2 NaNO3 NH4Cl BaSO4 Ka (Ionization Constant of Acid) 100% ionized 1.2 x 10-2 5.7x10-8 1.2x10-13 The oxide of which element will react with water to form the strongest acid? Given that HX is a stronger Bronsted acid than HY in aqueous solution, which is true of a M solution of NaX a It is less basic than a M solution of NaY b It is more basic than a M solution of NaY c It yields a neutral solution d It is more concentrated than a M solution of NaY The pH of a 1.0 x 10—3 M Ba(OH)2 25oC is a 2.7 b 3.0 c 11.0 d 11.3 Conjugate Base Cl— 10 Main Groups I II II IV I X W Y Z P V VI VII O Q R S T U M W M P R Z Which statement is a logical inference from the fact that a 0.10 M solution of potassium acetate KC2H3O2, is less alkaline than a 0.10 M solution of potassium cyanide, KCN? a b c d Hydrocyanic acid is a weaker acid than acetic acid Hydrocyanic acid is less soluble in water than acetic acid Cyanides are less soluble than acetates Acetic acid is a weaker acid than hydrocyanic acid 11.In the titration of 50.0 mL of 0.100 M benzoic acid (a monoprotic acid) with 50.0 mL of 0.100 M NaOH, the properties of the solution at the equivalence point will correspond exactly to the properties of a a 0.100 M sodium solution b a 0.0500 M sodium hydroxide solution c a 0.0500 M benzoic acid solution d a 0.0500 M sodium benzoate solution 12 13 A mixture of which pair of 0.1 M aqueous solutions would constitute a buffer? a NaOH and NaCl b HCl and NaOH c HCl and NaCl d NH3 and NH4NO3 Which electron transition is associated with the largest emission of energy? a b c d What these have in common? 20 a b c d 14 19 19 1- Ne F 24 Mg2+ 20 the same number of protons the same number of neutrons the same number of electrons the same size The number of neutrons in the nucleus of 13 a b c d e n=2 to n=1 n=2 to n=4 n=2 to n=3 n=3 to n=2 If an electron moves from one energy level in an atom to another energy level more remote from the nucleus of the same atom a energy is absorbed b energy is liberated c there is no energy change d the atom must assume a different ionic valence an e light of a at definite wave o length is m emitted of 21 A photon of light of 450 nm, when compar ed to light of wavele ngth 300 nm, has (1nm = 10-9 m) a 15 16 The orbitals of 2p electrons are often represented as being a elliptical b Pyramidal c Tetrahedral d dumbbell shaped e spherical The element in Period 5, Group 3A, has the outer electron configuration a 5s25p1 b 3s23p5 c 3s23p3 d a higher frequency 5s25p3 17 Which electron configuration is impossible? a 1s22s22p63s2 b 1s22s22p63s23p6 c 1s22s22p62d2 d 1s22s22p53s1 18 The element X occurs naturally to the extent of 20.0% 12X and 80.0% 13X The atomic mass of X is nearest a b c d 12.2 12.5 12.8 13.0 b c d 22 lower energy a greater velocity a shorter wavelength Which set of quantum numbers is possible for an electron in an atom? a n=3, l=0, ml=1, ms = -½ b n=2, l=2,ml= -2, ms = -½ c n=5, l=2, ml=2, ms =+½ d n=4, l=3, ml= -4, ms= -½ 23 A compound consisting of an element having a low ionization potential and a second element having a high electron affinity is likely to have a b c d 24 covalent bonds metallic bonds coordinate covalent bonds ionic bonds According to modern bonding theory the number of sigma (σ) and pi (π) bonds in the ethylene molecule H2C=CH2 is a l π and σ b c l π and σ l π and σ d e π and σ l π and σ 25 The number of σ bonds in N=N is a b c d 26 The elements in an ionic compound are held together by Standard Potentials Mg Mg2++2e Al  Al3++3e Zn  Zn2++2e FeFe2++2e Cu  Cu2++2e Ag Ag++ e 31 o E 2.37V 1.66V 0.76V 0.44V 0.34V -0.80V Using only the metals Mg, Al, Zn, Fe, Cu a 27 electrostatic forces of attraction b van der Waals forces c the spin of paired electrons d the formation of hybrid orbitals e an electron pair In every electrolytic and galvanic (voltaic) cell the anode is that electrode a b c d 28 at which oxidation occurs which attracts cations at whi ch elec tron s are sup plie d to the solu tion at which reduction occurs Metal X was plated from a solution containing cations of X The passage of 48.25 C deposited 31 mg of X on the cathode What is the mass of X (in grams) per mole of electrons? a 47 b 62 c 93 d 186 29 In a galvanic (voltaic) cell in which the reaction is Cd + 2+ Cu  Cu + Cd2+ and the ions are at unit concentration (activity), the cell potential is C d  C d 2+ + e - V C u  C u and Ag, together with their M salt solutions, a voltaic cell of the highest possible voltage would be constructed using electrodes of these metals a Mg and Ag b Mg and Fe c Zn and Cu d Al and Ag e Mg and Al + + e - 4 V a 32 V b c d e 30 0.4021 V 0.344 V 0.7461 V 0.3677 V In which reaction will an increase in total pressure at constant temperature favor formation of the products? a CaCO3(s)  CaO(s) + CO2(g) b H2(g) + Cl2(g)  2HCl(g) c 2NO(g) + O (g)  2NO (g) c + ] 33 b E = Eo 0.059/n log Q (Nernst equation ) [H+] = 1.0 M initially, P02 = 1.0 atm 4e + O2(g)+4H+ (aq) 2H2O(l) Eo=1.23V Based on the information above, which statement is correct? a n= 1, sin ce on e mo le of ox yg en is d The equilibri um constant for the gaseous reaction C+D  E + 2F is 3.0 at 50 oC In a 2.0 L flask at 50 oC are placed 1.0 mol of C, 1.0 mol of D, 1.0 mol of E, and 3.0 mol of F Initially, the reaction will a proceed at equal rates in both directions b proceed more rapidly to form E and F c proceed more rapidly to form C and D d not occur in either direction Compound H2O(l) H2O(g) 34 [ O value,] which less [ 1.23 H At 298 K the equi libri um cons tant for ∆Go —237 —229 H2(g) + ½ O2(g)  H2O(l) a i s l a r g e r t h a n t h e K e q f o r H ( g ) + ½ O ( g )   H O ( g ) b d will have a value of at equilibrium 2 c cannot be computed since data on O2 and COCl2(g)  CO(g) + Cl2(g) H2 are not provided will have the same value as the Keq for H2(g) + O2(g) H2O(l) b Consider the reversible system at equilibrium: 2CO + O2  2CO2 + heat When the temperature is increased at constant pressure d d 35 a b c d e 36 37 The numerical value of the equilibrium constant for any chemical change is affected by changing a the catalyst b the concentration of the products c the concentration of reacting substances d the pressure e the temperature 39 At a certain temperature, the equilibrium constant for the reaction 2HI(g)  H2(g) + I2(g) is 0.49 Calculate the number of moles of hydrogen produced when one mole of HI is placed in a L vessel at this temperature a 0.41 b 0.25 c 0.29 d 3.45 40 What is the [OH-] of a solution which is 0.18 M in ammonium ion and 0.10 M in ammonia? Kb = 1.8 x 10-5 a 1.3x10-3 b 1.0x10-3 c 1.3x10-5 d 1.0x10-5 41 What is the pH of a 0.10 M solution of a monoprotic acid, HA, with a Ka = 1.0 x 10-6? a 1.6 b 3.5 c 5.0 d 6.0 42 When 0.10 mol of a weak acid HA was diluted to one liter, experiment showed the acid to be 1% dissociated HA + H2O  H3O+ + AWhat is the acid dissociation constant, Ka? a x10-6 b x10-5 c l x10-3 d x105 Which solution has a pH less than 7.0? a M NH4Cl b M K2CO3 c M NaOCl d M NaOH What is the equilibrium constant expression for the gas phase oxidation of CO to CO2 by O2? a b 38 the CO2 concentration will be increased the CO2 concentration will be decreased the amount of each substance will be unchanged the amount of each substance will be increased the result cannot be predicted from the information given c K = [CO2]2 [CO][O2] K= [CO]2 [O2] [CO2] c K= [CO2]2 [CO]2 [O2] d K= [CO] [O2] [CO2] 43 Into an empty vessel COCl2(g) is introduced at 1.0 atm pressure whereupon it dissociates until equilibrium is established: 2COCl2(g)  C(graphite) +CO2(g) + 2Cl2(g) 44 a If x represents the partial pressure of CO2(g) at equilibrium, what is the value of the equilibrium constant, Kp? x.2x2 (1.0-2x)2 x x 2x2 (1.0-2x2) x (2x)2 (1.0- 2x)2 x (2x)2 (1.0—x)2 What is the pH of a 0.1 M NaF solution? Ionization constant for HF, Ka = x 10-4 a 2.1 b 5.9 c 8.1 d 9.1 45 a b c d 46 1.6x10-2 1.6x10-9 4.0x10-5 6.2x10-5 The addition of solid Na2SO4 to an aqueous solution in equilibrium with solid BaSO4 will cause a b c d 48 2.2x10-4M 9.0 x 10-4 M 4.5 x 10-4 M 9.5 x 10-3M Assume that standardized aqueous solutions of each of these are available NaOAc RNH3+ClRNH2 HOAc 52 The correct IUPAC name of N2O3 is a nitrogen oxide b nitrogen(II) oxide c nitrous oxide d dinitrogen trioxide 53 In which case is the substance with the given formula followed by its correct name? a KNO2 — potassium nitrate b FeCl3 — iron(III) chloride c FeS — iron(II) sulfite d Mg3N2 — magnesium nitrite e HClO — hydrochloric oxide 54 Balance the equation for the following reaction, using no fractional coefficients ? C +? HNO3  ? CO2 +? NO2 +? H2O Ionization Constant Kb = 5.6 x 10-10 Ka = 5.6 x 10-10 Kb=1.8x10-5 Ka=1.8x10-5 A buffer with a desired pH is 5.0 would be conveniently prepared by appropriate mixtures of a NaOAc and HOAc b HOAc and water c NaOAc and RNH2 d HOAc and RNH2 50 Which is the correct expression for the solubility product constant for Ag2CrO4? a Ksp = [Ag+]2 [CrO4 2-] b Ksp = [2Ag+]2 [CrO4 2-] c Ksp = [Ag+] [CrO42-] d Ksp = [Ag+] [CrO42-]2 e Ksp = [2Ag+] [CrO42-] no change in [Ba2+] in solution more BaSO4 to dissolve precipitation of more BaSO4 an increase in the Ksp of BaSO4 Substance 49 51 The solubility of BaCO3 is 7.9 x 10-3 g/L Calculate the solubility product, Ksp ignoring hydrolysis MW of BaCO3 197 g/mol a b c d 47 BaCrO4 253 g/mol a 1.2x10-10 b 2.2x10-5 c 2.8x10-3 d 7.8 xl0-6 What is the hydrogen ion concentration of a buffer solution containing 0.10 M NO 21- and 0.20 M HNO2? Ionization constant for Nitrous Acid, Ka = 4.5x 10-4 Which substance is most soluble in water? a C6H6 b CaCO3 c C2H5OH d CO2 The solubility of BaCrO4 in water is 2.8 x 10-3 g/L what is the Ksp of the salt? MW of 55 The sum of the coefficients in the balanced equation is a b c d 12 e 16 Complete and balance the equation for the reaction, where the reactants are in aqueous solution Use no fractional coefficients ? Na3PO4 + ? Ba(NO3)2  ? + ? The number of moles and formula of the product containing Ba are a 3NaNO3 b BaPO4 c Ba(PO4)2 d Ba2P3 e Ba3(PO4)2 56 According to the kinetic molecular theory, a b c d e 57 b c d e 59 attractive forces between gas molecules are negligible attractive forces between gas molecules are appreciable the average kinetic energy of the molecules of a gas is proportional to the absolute temperature increasing the molecular concentration, at constant temperature, means increasing the number of collisions between molecules and container collisions between gas molecules are perfectly elastic The Kelvin temperature of one liter of gas is doubled and its pressure is tripled, volume will then be a l/6 L b 2/3 L c 3/2 L d L Which gas, present in the same closed system, has the greatest average kinetic energy at a given temperature? a b c d A sample of neon occupies a volume of 27.3 L at STP What would be the neon volume at 177 oC and 0.100 atm pressure? a b c d 177 L 350 L 422 L 450 L 61 Under the same conditions of temperature and pressure, the gas whose molecules possess the highest average speed is a H2O b O2 c F2 d Ne 62 What is the volume of 2.00 mol of helium gas at 27 oC and 3.00 atm? The volume of a given mass of gas varies inversely with pressure, provided that the temperature remains constant because a 58 gaseous molecules are continuously in random motion and collisions are perfectly elastic the absolute temperature of a gas depends on its molar mass the pressure exerted on a gas affects the speed of its molecules gaseous molecules can travel in straight or curved paths all gaseous molecules are diatomic 60 a b c d 63 6.1x10-2L 1.48L 16.4L 44.8 L Real gases are most like ideal gases at a b c d high pressure and high temperature low pressure and low temperature high pressure and low temperature low pressure and high temperature 64 500 mL of a gaseous compound has a mass of 0.9825 g at 0oC and 760 mmHg What is the approximate molar mass of the compound? a 19.7 b 38.7 c 44.0 d 58.9 65 The partial pressures of a gaseous mixture are given in the table What is the mole percent of hydrogen? Hydrogen neon carbon dioxide None; the average kinetic energy is the same for each gas a b c d hydrogen carbon dioxide methane ethylene 20.0 25.8 38.8 41.7 Partial Pressures 200 mmHg 150 mmHg 320 mmHg 105 mmHg 66 67 It is desired to collect enough oxygen over water at 25 oC and 750 mmHg barometric pressure to be equivalent to L of pure oxygen at oC and 760 mmHg The vapor pressure of water at 25 oC is 23.5 mm The volume collected is a L (298/273)(750/760) b L (273/298)((750-23.5)/(760-23.5)) c L (273/298)((750-23.5)/760) d L (298/273)(760/(750-23.5)) 71 The following mechanism has been proposed for the formation of ethylbenzene: CH3CH2Br + AlBr3  AlBr -4+ CH3CH +2 + CH3CH2+ + C 6H 6 C H6 CH CH + C6H6CH2CH + AlBr AlBr3 + HBr + C6H5CH2CH3 Which substance serves as the catalyst? Methane, CH4, diffuses in a given apparatus at the rate of 30 mL/min At what rate would a a AlBr3 b CH3CH2+ gas with a molar mass of 100 diffuse under the same conditions? MW of CH4 = 16 g/mol a 0.77 mL/min b 30 mL/min c 6.7 mL/min d 75 mL/min e 12.0 mL/min 68 The Arrhenius equation, k= AeE/RT expresses the relationship between the reaction rate constant, k, and the energy of activation, E The probability that colliding molecules will react a increa ses with increa sing energ y of activa tion b depends only on the empirical constant, A c increases with decreasing temperature d decrea ses with increa sing energy of activatio n 69 The rate law for the reaction A+BC+D is first order in [A] and second order in [B] If [A] is halved and [B] is doubled, the rate of the reaction will a b c d 70 remain the same be increased by a factor of be increased by a factor of be increased by a factor of The addition of a catalyst in a chemical reaction a increases the concentration of products at equilibrium b increases the fraction of reactant molecules with a given kinetic energy c provides an alternate path with a different activation energy d lowers the enthalpy change in the overall reaction 85 The fact that BCl3 is a planar molecule while NCl3 is pyramidal can be explained several different ways Which is the best rationalization? a b c d 86 Nitrogen is more electronegative than boron The nitrogen atom in NCl3 has a lone pair of electrons whereas the boron atom in BCl3 does not The nitrogen atom is smaller than the boron atom The boron atom in BCl3 is sp3 hybridized, while the nitrogen atom in NCl3 is sp2 hybridizes The geometry for SeF + is a trigonal pyramidal b tetrahedral c square planar d rectangular planar isotope? a b c d 91 Which of these molecules is the most polar? (X and Y are two different elements, Y being the more electronegative.) a b c d X2 Y2 X—Y—X X—Y X X e Y—X X 92 87 days days 12 days 16 days The Lewis structure of BrF5 is F F F Br F F In the beta emission of a species such as 14 6C the process may be considered as a b c d the change of a proton into a neutron the change of a neutron into a proton the same mode of decay as electron capture neutrino absorption by the nucleus The molecular structure of BrF5 is a b c d 88 90 93 PCl3 ClO3CO32NH3 PH3 A molecule of the type ML4 consists of four bonding pairs of electrons and no lone pairs Which structure would it be expected to assume? a square planar b tetrahedral c linear d square pyramidal A sample of a radioactive isotope initially contains 20 x 1010 atoms After 16 days, x 1010 atoms remain What is the half-life of the Which compound is a paraffin (methane series) hydrocarbon? a b c d e Which is planar? a b c d e 89 square pyramidal trigonal pyramidal trigonal bipyramidal octahedral 94 lsobutane differs from butane in that the former a b c d e 95 C5H12 C5H11OH (C2H5)2O C6H6 C6H5Cl has a higher molecular weight has a different percentage composition is not a saturated hydrocarbon has a different empirical formula has a different structural formula Which has the highest boiling point? a b c d n-butane C4H10 n-heptane C7H16 n-hexane C6H14 n-pentane C5H12 General Chemistry II Sample Test bank 96 Page 14of 27 The reaction between acetic acid and ethyl alcohol is classified as the magnesium acts as a reducing agent How many electrons does each magnesium atom lose? CH3COOH + C2H5OH  CH3COOC2H5 + H2O 97 a b c d saponification addition esterification hydrolysis Manganese has the oxidation number of +5 most polarizable? a b in c a Na+ 3b O2d a.4 [MnF6] c Fe b.6 Mn2O7 c [MnO4]2d Mg2+ 1102 d.Which of these [Mn(CN) 6] isoelectronic ions is the 103 98 The highest oxidation number of vanadium is exhibited in a b c d e 99 VO2+ VBr4 NH4VO3 V2(SO4)3 V(CN) 3— Fe(s) + Cu2+ (aq)  Cu(s) + Fe2+ (aq) Which statement is true for the reaction? a b c d 100 The greatest oxidizing power (tendency to gain electrons) is shown by a b c d 104 Cu2+ is oxidized Cu2+ gains in oxidation state Cu2+ is reduced Fe(s) is reduced Standard Potentials Na Na+ + e Al  Al3++3e Sn2+Sn4++2e 21—  l2+2e 2F—F2 + 2e Na+ Al Sn4+ F2 Which metal will reduce copper(ll) ions but not zinc ions? Which is the strongest oxidizing agent? Standard Potentials Na  Na+ + e Cd  Cd2+ + 2e H2  2H+ + 2e Ag Ag+ + e Eo 2.71 V 0.40 V 0.00 V -0.80 V o E 2.7 1.6 -0.1 -0.5 -2.8 General Chemistry II Sample Test bank a b Na c + Cd0 Hd.2 Ag+ 101 In this reaction 3Mg + 2HNO3(dilute) + 6H 3Mg2+ + 2NO + 4H2O a b c d Na Hg Pb Ag Standard Potentials Na  Na+ +e Zn  Zn2++2e Fe  Fe2+ + 2e Pb  Pb2++2e H2  2H++ 2e Cu  Cu2++2e Hg  Hg2++2e Ag  Ag+ +e o E 2.71 V 0.76 V 0.4 V 0.13 V 0.00 V -0.34.V -0.85 V -0.80 V Page 15of 27 105 A metal, M, forms an oxide of formula M2O3 The ground state valence shell electron configuration of the M atom is a b c d 106 109 Based on their positions in the periodic table, which is most likely to replace selenium, Se, in a biological system? a Te b Br c As d I 113 Which conditions favor the high solubility of a gas in a liquid? a high pressure, high temperature b high pressure, low temperature c low pressure, high temperature d low pressure, low temperature 114 Ionic compounds in the solid state at room temperature are generally characterized by their a ability to conduct an electric current b high vapor pressures c solubility in polar solvents d solubility in nonpolar solvents e low melting points 115 Which precipitate will not dissolve in aqueous HCl solution? a AgBr b BaCO3 c CaSO3 d Fe(OH)3 e ZnS 116 A cellophane bag, which acts as a membrane permeable only to water, contains a M sugar solution The bag is immersed in a M sugar solution What will happen? A3N A3N2 AN AN2 In which pair of particles is the first member larger than the second member? a b c d Li+ ; Be2+ Li+ ; Na+ Li+ ; Li Be ; Mg Which would be expected to be the most electronegative? a b c d P As Si Al a 110 Predict which element would have the largest difference between its first and second ionization energies a Sodium b Phosphorus c Silicon d magnesium NaCl(crystal) + energy  Na+(g) + Cl—(g) Cl(g) + energy Cl+ + e Cl(g) + e  Cl—(g) + energy Cl— g) + H+(g)  HCl(g) + energy 112 Use this section of a periodic table A E Q R If atoms of R have one “d” type electron, what is the formula for a nitride of element A? a b c d 108 ns np np6 4s13d10 4f7 GaSe GaSe2 Ga2Se Ga2Se3 In which reaction is the energy term referred to as the ionization energy? a b c d From your knowledge of the periodic nature of the elements, what formula would be anticipated for gallium selenide? a b c d 107 111 b c d e The bag will soon contain more solution that will be are concentrated than M The bag will soon contain more solution that will be less concentrated than M The bag will lose sugar and the solution in it will become less concentrated The bag will lose water and the solution in it will become more concentrated There will be no change 117 a b c d 118 4.00x10–3 m 5.00x10–2 m 5.00 x 10–3 m 4.00 x 10–1 m 123 What is the mole fraction of water in 200 g of 95% (by mass) ethanol, C2H5OH (mw = 46.0 g/mol)? a b c d 119 a b c d e If 0.400 g of a substance R (MW = 80.0 g/mol) is dissolved in 100 g of liquid Q, what is the molality of the solution? 0.050 0.12 0.56 0.88 When dilute aqueous solutions of lead(II) nitrate and potassium bromide are mixed, a precipitate is observed The products of this reaction are a b c d 124 A 0.10 m aqueous solution of HF shows a freezing point of - 0.198 oC What is the percent dissociation of HF? Molal freezing point 40 g./mol 200 g/mol 100 g./mol 400 g/mol 128 g./mol Pb2+(aq) + Br 1- (aq) + KNO3(s) Br2(aq) + NO2(g) + PbK2(s) PbO(s) + K+(aq) + Br1-(aq) + NO2(g) PbBr2(s) + K+(aq) + NO3 1-(aq) Assuming ideal behavior, what is the vapor pressure of a solution of 16.0 mol of carbon tetrachloride and 4.00 mol of dioxane at 23 oC? constant, Kf for water = 86 oC/m a b c d 6.4% 10% 20% 98% 120 A 0.10 m solution of MgSO4 freezes at -0.245oC instead of x (- 0.186 oC) 122 When one mole of as predicted for naphthalene is ideal behavior This dissolved in 1000 g of deviation from benzene, the freezing ideality can best be point changes from explained on the 5.51 oC to 0.41 oC basis of When 20 g of an unknown organic a interionic compound is dissolved attraction in 500 g of benzene, b hydrogen the freezing point of bonding this solution is c the Le 5.00 oC What is the Chatelier molar mass of the principle unknown organic d the solubility compound? product constant 121 Which aqueous solution has the smallest freezing point depression? a b c d 0.2 m Ca(NO3)2 0.2 m MgSO4 0.2 m CH3OH 0.2 m K3PO4 a b c d 125 b c d What is the empi rical form ula for the subst ance with this analy sis: Na=5 4.0% , B=8 50%, O=3 7.5% a 126 Na3BO3 Na4BO4 Na2B2O3 NaB2O2 A hydrocarbon undergoes complete combustion to give 0.44g of CO2 and 0.27 g of H2O What is the simplest (empirical) formula of the hydrocarbon? a b c d C44H27 CH4 C2H3 CH3 127 128 A 6.80 g coin was dissolved in nitric acid and 6.21 g of AgCl was precipitated by the addition of excess sodium chloride, Calculate the percentage silver in the coin Ag+(aq) + Cl1-(aq) AgCl(s) a 24.7% b 68.7% c 75.3% d 91.3% 133 Which change is likely to be accompanied by the greatest increase in entropy? a b c d 134 A 40- mL portion of a 0.1 M MgSO4 solution contains how many grams of MgSO4? a 120 g N2(g) + 3H2(g)  2NH3(g) (at 25 oC) Ag+(aq) + Cl1-(aq)  AgCl(s) (at 25 oC) CO2(s)  CO2(g) (at - 70 oC) H2O(g)  H2O(l) (at 100 oC) When 45.0 g of an alloy at 100.0 oC is dropped into 100.0 g of water at 25.0 oC the final temperature is 37.0 oC What is the specific heat of the alloy? (for water, specific heat = 4.184 J g1o -1 b.C )24 g c 0.96 g d 0.6 g e 0.48 g a b c d 129 An aqueous solution containing 49 g of 135 d 112 sulfuric acid per liter has a 132 What volume of ammoni concentration of a 0.50 M measured at STP, will b 1.0M be produced by the c 4.9% by decomposition of two mass moles of ammonium d 4.9M carbonate? (NH4)2CO3(s)  130 One hundred 2NH3(g) + CO2(g) + milliliters of a H2O(g) solution of oxalic a 22.4 L acid, (COOH)2, is b 33.6 L neutralized with c 44.8 L 50.0 mL of 0.750 d 89.6 L M KOH solution e 112 L What is the molarity of the oxalic acid solution? a 0.099 M b 0.375 M c 0.188 M d 0.750 M e 0.333 M 131 How many L of CO2 gas at STP can be obtained by burning one mole of C3H8? C3H8(g) + O2(g) 3 CO2(g) + 4H2O(g) a 11.2 b 44.8 c 67.2 combustion of C2H6 in kJ mol1 ? rived from coolin g one gram of steam at 100 o C to water at 50 o C than from coolin g one gram of liquid water at 100 o C to 50 oC becau se Reaction H2(g) + ½ O2(g)  H2 C2H4(g) + H2(g)  C C2H4(g) + O2(g) CO H2O(g) a b c d 136 –1275 kJ –31561 kJ –1558 kJ +1834 kJ Given these equations SO2( g)  O2(g) + S(s) ∆Ho = +300 kJ 2SO2 (g) + O2(g)  2SO3 (g) ∆Ho =200 kJ a b c calculate the heat of formation of SO3(g) a –500 kJ.mol-1 b +100 kJ.mol-1 c –400 kJ.mol-1 d +200 kJ.mol-1 137 M or e he at is de d water is a poor thermal conductor the steam is hotter than the water the stea m occu pies a great er volu me than the water the densi ty of water is great er than that of stea m e the heat of condensation is evolved 138 Calculate the value of (in kJmol-1) for the reaction 142 N2(g) + 3H2(g) 2NH3(g) Bond Energies H—H N=N N—H Which nuclear equation is properly balanced? a 4He + 9Be  12C + 1H b 4He + 14N  17O + 1H c 4He + 24Mg  27Si + 1H (kJ mol-1) 435 946 (in N2) 389 d -1 14 N + e  14 O 143 What is the correct reading for the buret? 32 a b c d 139 140 2340 kJ of heat absorbed 213 kJ of heat absorbed 2340 kJ of heat evolved 83 kJ of heat evolved When Al2O3(s) is formed from the elements at standard conditions, the values of ∆Ηo and ∆Go at 298 K are -1617 kJ.mol-1 and -1577 kJ.mol-1, respectively The standard entropy of formation per mole, in joules per degree, will be a -315 b -134 c - 93.3 d 0.0933 e +15.7 Vaporization of a liquid is an example of a process for which a ∆H, ∆S, and ∆G are posit ive at all b c d 141 tempera tures ∆H and ∆S are positive ∆G is negative at low temperat ures, positive at high temperat ures ∆H=∆S Consider the boiling point of a series of hydrogen compounds The abnormally high boiling point for water is due to 33 a b c d 144 a 32 mL 32.2 mL 32.26 mL 33.74 mL e m pe tu re s b A particular chemical reaction has a negative ∆H and negative ∆S Which statement is correct? T h e r e a c t i o n i s s p o n t a n e o u s a t a l l t c T h e r e a c ti o n i s n o n s p o n t a n e o u s a t a ll t e m p e r a t u r e s T h e r e a ct d io n be co me s sp on tan eo us as te m pe rat ur e inc rea ses Th e reacti on beco mes spont aneo us as temp eratur e decre ases 145 Which line in the diagram represents the activation A energyDfor a forward reaction? B a b c A B C E C BP d D Reaction Coordinate H2O H2S H2Se H2Te a b c d extensive hydrogen bonding its low dipole moment the extreme stability of the compound the high electronegat ivity of hydrogen H 146 The group —C=O is characteristic of a aldehydes b ketones c alcohols d esters e acids 147 Uranium—234 undergoes spontaneous radioactive decay to give an alpha particle and a new nucleus, X U  4He + X 234 What is X? 150 Consider the phase diagram of a pure compound Which statement applies? a 230 U 90 b 230 Th P 90 c 238 U 238 94 d Pu AC 94 148 a b c d Which is classifi ed as an alkene ? O B CH3— CH2— C—H CH3C H2CH3 CH3— C=C H CH2 HC CH2 H C C H C H 149 a An exampl e of an organi c acid is O CH3C H2CO CH3 O b CH3CH2COH O c CH3CH2CNH2 O d CH3 CH2CH o u l d Temper ature a b The pat hA C repr ese nts subl ima tion f i r s t l i q u e f y F o l l o w i n g a n d t h e n t h e p a t h A  B  C t h e c o m p o u n d w c v a p o r i z e I f t h e c o m p o u n d i s i n s t a te A , c o nt in u e d re d u ct io n of th e pr es su re (a t c o ns 152 d 151 a b c d e Which is the formula of an alcohol? CH3CH2CH2 — O—CH3 CH3CH2CH2C H2 – O H O c CH3 CH2 —C —CH3 O d CH3CH2CH2C —H Which choice best indicates the degree of correctness of this statement? “The boiling point of normal propanol is lower than the boiling point of turpentine.” Temperature n-propanol Water Turpentine a b tant temp eratu re) will cause it to melt None of these statements is correct 0oC 3.4 4.6 2.1 Vapor Pressure of Substances in mm 20oC 50oC 80oC 95oC 14.5 87.2 376 697 17.6 92.0 354.9 4.4 17.0 61.3 The statement is true The statement is probably true; additional data would be needed for a final decision It is impossible to judge the statement because the data are insufficient The statement is probably false; additional data would be needed for a final decision The statement is false 153 For the reaction 2H2O2 2H2O +O2 Which plot confirms that the rate is first order with respect to H2O2? a b [H2O2] d [H2O2]2 1/[H2O2] time 154 c time log[H2O2] time time Sulfur dioxide can be described by the structures: S O S O O O This implies that a b c d 155 the two bonds in SO2 are of equal length, and the electronic distribution in the two SO bonds is identical the single bond is longer than the double bond and the electronic distribution in the two SO bonds is different an electron pair in the SO2 molecule alternates back and forth between the two sulfur— oxygen electron pairs so that the two different bonds seem to exchange positions the SO2 molecule revolves so that the two different bonds seem to exchange positions The graph shows how the vapor pressure of liquid A and of liquid B changes with the temperature Select the choice that best indicates the degree of correctness of this statement: “The normal boiling point of liquid B is 78 0C.” 1000 900 Va 800 po r pr es su re m m A 600 B 400 300 200 100 20 40 60 80 100 120 Temperature oC a b c d e The statement is true The statement is probably true; additional data would be needed for a final decision It is impossible to judge the statement because data are insufficient The statement is probably false; additional data would be needed for a final decision The statement is false 156 The isomerism represented by H H H H H HH — C—C—C—O—H and H—C—C—O—C—H H a b c d 157 a b c d 158 H H H H H cis—trans optical positional geometric In a sample of a nearly ideal gas, this graph could represent a plot of V vs T at a given constant P P vs T at a given constant V P vs V at a given constant T PV vs P at a given constant T A mixture of 100 g of K2Cr2O7 and 200 g of water is stirred at 60 oC until no more of this salt dissolves The resulting solution is decanted (poured off) and cooled to 20 oC What mass of K2Cr2O7 crystallizes from the solution during the cooling? 80 60 Solubility (g/100 mL) 40 20 a b c d e 159 20 40 60 80 Temperature in oC 100 24 g 31 g 43 g 58 g 86 g The height of the mercury in the right arm open to atmospheric pressure (760 mmHg) is 100 mm and the height in the left arm is 120 mm gas What is the pressure of the gas in the bulb? a b c d 20 mmHg 640 mmHg 740 mmHg 780 mmHg 120 mm 100 mm Key to Answers Q# Ans Q# Ans Q# Ans Q# Ans Q# Ans 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 D B A A D D A A D A D D C D D A C C A A B C D C A A A B D C A B C A B 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 E C C C D B B A C B B C A C A A D B D E A D B D D A C D C B D E D B C 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 A C D D B D C C E A D C D A B A A C B B D B A E B C D C C D B B D C A 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 D B A A A B A B C A B B B A A C D D D A D B E A C C D C B C C E D B B 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 A B C D A A B D B D B A D A A C C D C ... highest boiling point? a b c d n-butane C4H10 n-heptane C7H16 n-hexane C6H14 n-pentane C5H12 General Chemistry II Sample Test bank 96 Page 14of 27 The reaction between acetic acid and ethyl alcohol... Cd2+ + 2e H2  2H+ + 2e Ag Ag+ + e Eo 2.71 V 0.40 V 0.00 V -0.80 V o E 2.7 1.6 -0.1 -0.5 -2.8 General Chemistry II Sample Test bank a b Na c + Cd0 Hd.2 Ag+ 101 In this reaction 3Mg + 2HNO3(dilute)... d low pressure, low temperature 114 Ionic compounds in the solid state at room temperature are generally characterized by their a ability to conduct an electric current b high vapor pressures

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