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Consider the reaction between Mg(s) and HCl(aq) to produce aqueous magnesium chloride and hydrogen gas. How many liters of hydrogen gas at STP will be produced when 12.15 g of magnesium reacts with an excess of hydrochloric acid? A)1.00 L […]

Select the correct molecular structure for the given species from the choices below: SiH4 A)pyramidal B)tetrahedral C)square planar D)octahedral E)none of these Referring to the structures below, which statement is true? A) I and II have different molecular formulas. B) […]

Determine (a) the rate equation and (b) the rate constant for the hypothetical reaction A+B–>C given the following initial concentrations and initial rate data. Which charge(s) on an N2ion would give a bond order of 2.5? A)-2 B)-1 C)+1 D)+2 […]

When ignited, solid ammonium dichromate decomposes in a fiery display. This is the reaction for a “volcano” demonstration. The decomposition produces nitrogen gas, water vapor, and chromium(III) oxide. The temperature is constant at 25°C Determine Suniv° (in kJ/mol K). A) […]

The following questions refer to the hypothetical reaction A + B –> products. The kinetics data given can be analyzed to answer the questions. What form will the pseudo-rate law have? A)Rate = k'[A]x B)Rate = k'[B]y C)Rate = k'[A]x[B]y […]

The bond order in the NO molecule is A)1 B) C)2 D) E)3 The bond angles about the carbon atom in the formaldehyde molecule, H2C=O, are about: A)120° B)60° C)109° D)180° E)90° Answer: A The standard temperature for gases is […]

A sample of a gas occupies a volume of 2.62 liters at 25 °C and 1.00 atm. What will be the volume at 50.0 °C and 2.00 atm? A)1.42 liters B)2.62 liters C)4.83 liters D)5.68 liters E)10.5 liters Use the […]

Consider the following information about the diprotic acid, ascorbic acid. (H2As for short, molar mass 176.1) H2As HAs–+ H+pKa= 4.10 (Ka= 7.9×10-5) HAs– As2-+ H+pKa= 11.79 (Ka= 1.6×10-12) The titration curve for disodium ascorbate, Na2As, with standard HCl is shown […]

For each group of compounds listed, which is the strongest acid? I. HIO2, HIO3, HIO4 II. H2Se, H2S, H3As III. HPO2, HClO2, HBrO2 A) I. HIO2, H2Se, HBrO2 B) I. HIO4, H2Se, HBrO2 C) I. HIO2, H3As, HPO2 D) I. […]

Which has these types of electromagnetic radiation arranged in order of decreasing energy? A)visible, ultraviolet, x-ray B)radiowaves, visible, ultraviolet C)ultraviolet, visible, infrared D)x-ray, visible, ultraviolet E)none of these The following data were obtained for the reaction of NO with O2. […]

The Lewis structure for H3BO3is A) B) C) D) E) Which of the following electron distributions among the molecular orbitals best describes the NO molecule? A)2 2 4 2 4 2 B)2 2 4 2 4 1 C)2 2 4 […]

What is the overall reaction for the production of hydrogen from methane and water? A) CH4(g) + H2O(g) –> CO(g) + 3 H2(g) B) CO(g) + H2O(g) –> CO2(g) + H2(g) C) CH4(g) + 2 H2O(g) –> CO2(g) + 4 […]

A sample of nitrous oxide, N2O, occupies 16,500 mL at STP. What is the mass of the sample? A)18.9 B)22.1 C)22.8 D)32.4 E)46.0 Tetracyanoethylene has the skeleton shown below: From its Lewis structure determine the following: How many of the […]

Determine the value of k (without units) for the reaction: C2H4Br2+ 3KI –> C2H4+ 2KBr +KI3, given the initial rate data below? A)0.149 B)0.538 C)0.0830 D)0.299 E)0.598 The following data were collected for the decay of HO2radicals: Which of the […]

What is the bond order of Ne2? A)0 B) C)1 D) E)2 Using the following thermochemical data, calculate DHf° of Tm2O3(s). 2TmCl3(s) + 3H2O(l) –> Tm2O3(s) + 6HCl(g)DH° = 388.1 kJ/mol 2Tm(s) + 3Cl2(g) –> 2TmCl3(s)DH° = -1973.2 kJ/mol 4HCl(g) […]

For each of the following solutions, describe the deviation with respect to Raoult’s Law. acetone (C3H6O) and water A)relatively ideal B)positive deviation C)negative deviation D)more information needed E)none of these How many of the following molecules or ions are linear? […]

Which metal, Al or Ni could reduce Zn2+to Zn(s) if placed in a Zn2+(aq) solution? A) Al B) Ni C) Both Al and Ni would work. D) Neither Al nor Ni would work. E) Cannot be determined. Which of the […]

Consider the following data concerning the equation: The average value for the rate constant k (without units) is A)2710 B)2.74 x104 C)137 D)108 E)none of these Using the following electronegativity values: C2.5Cl3.0 H2.1O3.5 select from the following group the molecule […]

For a reaction in which A and B react to form C, the following initial rate data were obtained: What is the rate law? A)Rate = k[A][B] B)Rate = k[A]2[B] C)Rate = k[A][B]2 D)Rate = k[A]2[B]2 E)Rate = k[A]3 Select […]

Using the following bond energies: BondBond Energy (kJ/mol) CºC839 C−H413 O=O495 C=O799 O−H467 estimate the heat of combustion for one mole of acetylene: C2H2(g) + O2(g) –> 2CO2(g) + H2O(g) A)1228 kJ B)−1228 kJ C)−447 kJ D)+447 kJ E)+365 kJ […]

Given the following information: Br2bond energy = 193 kJ/mol F2bond energy = 154 kJ/mol Br2(g) + F2(g) –> BrF3(g)DH° = €384 kJ/mol calculate the Br-F bond energy. A)244 kJ/mol B)237 kJ/mol C)712 kJ/mol D)128 kJ/mol E)none of these Describe the […]

For the complete combustion of 1.000 mole of methane gas at 298 K and 1 atm pressure, DH° = -890.4 kJ/mol. What will be the heat released when 1.85 g of methane is combusted under these conditions? A)-103 kJ B)103 […]

Which 1strow transition metal demonstrates the most oxidation states? A) Fe B) Ti C) Cr D) V E) Mn Select the correct molecular structure for the given species from the choices below: XeF6 A)pyramidal B)tetrahedral C)square planar D)octahedral E)none of […]

The questions below refer to the following system: When cobalt(II) chloride is added to pure water, the Co2+ions hydrate. The hydrated form then reacts with the Cl–ions to set up the equilibrium shown here. Which statement below describes the change […]

Which of the following 0.01 M solutions has the highest pH? A) HOAc B) NaOAc C) Na2CO3 D) H2CO3 E) NaHCO3 The oxidation of Cr3+ to CrO4 2- can be accomplished using Ce4+ in a buffered solution. The following data […]

Consider the molecule: Specify the hybridization of each carbon atom. C-1C-2C-3C-4C-5 A)sp2sp2sp2sp3sp B)sp2sp2sp2sp3sp3 C)sp2sp2sp3sp3sp2 D)sp2sp2sp3sp3sp3 E)sp2sp sp sp2sp How many of the following apply to fibrous proteins? A) 1 B) 2 C) 3 D) 4 E) 5 Answer: B In […]

Which represents the ground state for N? A)option a B)option b C)option c D)option d E)option e Choose the member of each set that best matches the label. More metallicBe or Ba More covalentN2O(g), MgO(s) Highest electronegativityO, S, Br A)Be, […]

Consider the compound crotonaldehyde, whose skeleton is: How many nonbonding electrons appear in the Lewis structure of this molecule? A)2 B)4 C)6 D)8 E)10 Determine the units of k for the reaction: C2H4Br2+ 3KI –> C2H4+ 2KBr +KI3, given the […]

Phosphorus, P4, can be prepared from calcium phosphate by the reaction The molar mass for each reactant is shown below the reactant, and the mass of each reactant for this problem is given above. Which reactant is the limiting reagent? […]

The mass of 1.12 liters of gas Y at STP is found to be 6.23 g. The molar mass of gas Y is A)56.0 g/mol B)89.0 g/mol C)125 g/mol D) g/mol E)157 g/mol Consider the freezing of liquid water at […]

Select the correct molecular structure for the given species from the choices below: PF6¯ A)pyramidal B)tetrahedral C)square planar D)octahedral E)none of these Of the following, which form compounds? A) I, II B) II, III C) I, II, III D) II, […]

How many places on the ligand EDTA can simultaneously bind to a single metal atom? A) 1 B) 2 C) 3 D) 4 E) 6 Which Group 3A element has the most stable +1 oxidation state? A) B B) Al […]

You discover that the complex decomposes in water. You dissolve 0.1000 g of the complex in H2O and add excess NaHg(SCN)4, which precipitates Co(II) as CoHg(SCN)4(s). After the precipitate is washed and dried, its mass is 0.1102 g. How many […]

Which of the following nuclides would be most expected to undergo a-decay? A) 86As B) 127I C) 252Es D) 9C E) 171Ir In the reaction: CaO(s) + SO2(g) –> CaSO3(s) A) Ca2+acts as a Lewis acid and SO3 2-acts as […]