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|---|---|---|---|---|---|---|---|---|---|---|---|---|
Chemistry | Use the arrangement of atoms suggested in the skeleton structure above to construct the Lewis structure for the SO$_3$ molecule. Which of the following statements about this molecule is incorrect?
| 3 | [
"Sulfur trioxide has three resonance structures.",
"Sulfur trioxide has a planar triangle shape.",
"Sulfur trioxide is nonpolar.",
"The S–O bond order is 5/3."
] | |||||||||
Chemistry | Use the arrangement of atoms suggested in the skeleton structure above to construct the Lewis structure for the sulfite ion. Be sure to minimize the formal charges. Which of the following statements is incorrect?
| 2 | [
"The sulfite ion has a double bond.",
"The sulfite ion has a triangular pyramid shape.",
"The sulfite ion is nonpolar.",
"The S–O bond order is 4/3."
] | |||||||||
Chemistry | Ethanoic acid (\ce{HC2H3O2} \quad \text{or} \quad \ce{CH3CO2H} \quad \text{or} \quad \ce{CH3COOH}
) has a much lower vapor pressure than ethanol (\ce{CH3CH2OH}). What is the most reasonable explanation?
| 1 | [
"The polarizability of two oxygen atoms increases the London forces of attraction in ethanoic acid compared with ethanol.",
"Hydrogen bonding in ethanoic acid is the strongest attractive force and is mainly responsible for the observed data.",
"Ethanol has an –OH group and can hydrogen bond; therefore, the Lond... | |||||||||
Chemistry | Vitamin C is oxidized slowly to dehydroascorbic acid by the oxygen in air. It is catalyzed by ions such as \ce{Cu^2+} and \ce{Fe^3+}
. The reaction can be followed by measuring the ultraviolet absorbance at 243 nm.
Which of the following is the best interpretation of the data given above?
| 0 | [
"The data support a first-order reaction.",
"The data support a second-order reaction.",
"The data support a zero-order reaction.",
"The overall order is 14."
] | |||||||||
Chemistry | Choose the description of the point on the distribution curve that is the most plausible.
| 1 | [
"Point A represents absolute zero where all motions stops.",
"Point C is proportional to temperature",
"Point B is where the transition state occurs.",
"At point D, the products of the reaction are found."
] | |||||||||
Chemistry | Three 1-liter flasks are connected to a 3-liter flask by valves as shown in the diagram above. The 3-liter flask has the relative number of helium atoms as indicated. At the start, the entire system is at 585K. The first flask contains oxygen; the second contains hydrogen, and the third contains nitrogen. The pressure ... | 1 | [
"1.0 atm",
"2.0 atm",
"3.0 atm",
"4.0 atm"
] | |||||||||
Chemistry | A mass spectrum of a naturally occurring sample of an element is shown above. What is the element?
| 0 | [
"Cl",
"S",
"Ar",
"There are two peaks, so there must be two compounds."
] | |||||||||
Chemistry | In the diagram above, which labeled arrow is pointing toward a covalent bond and which is pointing toward a hydrogen bond?
| 3 | [
"1 2",
"2 1",
"3 4",
"4 3"
] | |||||||||
Chemistry | Space-filling representations of carbon tetrachloride and carbon tetrabromide are shown above. The carbon can be seen in the carbon tetrachloride and is hidden by the bromine in carbon tetrabromide. Which of the following is the most reasonable statement? (Assume that the temperatures of CCl$_4$ and CBr$_4$ are the sam... | 1 | [
"CCl$_4$ has a higher surface tension compared with CBr$_4$",
"CCl$_4$has a higher vapor pressure compared with CBr$_4$.",
"CCl$_4$ has a higher boiling point compared with CBr$_4$.",
"CCl$_4$ has a higher viscosity compared with CB$_4$."
] | |||||||||
Chemistry | Which of the labeled arrows in the diagram above represents the strongest intermolecular force of the four indicated?
| 0 | [
"Arrow A",
"Arrow B",
"Arrow C",
"Arrow D"
] | |||||||||
Chemistry | According to the data in the table above, which of the compounds has the strongest intermolecular forces?
| 0 | [
"Propylamine",
"Ethyl methyl ether",
"Trimethyl amine",
"Ethyl methyl amine"
] | |||||||||
Chemistry | Each of the ions in the table form stable oxides (Na$_4$O, CdO, and La$_4$O$_3$). Lanthanum oxide, La$_4$O$_3$, has a melting point significantly higher than that of the other oxides. Which of the following is the best explanation of why this is true?
| 2 | [
"Lanthanum is a lanthanide element and the melting points of these elements are always high.",
"There is more oxygen in the formula La$_4$O$_3$ than in the other formulas.",
"Lanthanum had the highest charge; therefore, it has the highest lattice energy.",
"Alkali metals like sodium and transition metals lik... | |||||||||
Chemistry | The diagram above shows the structure of molecules of CS$_2$ and COS. The boiling point of COS is 223 K, and the boiling point of CS2 is 319 K. Which of the following is the best explanation of why the boiling point of CS$_2$ is higher?
| 0 | [
"The molar mass of CS$_2$ is greater.",
"COS has weaker covalent bonds than CS$_2$.",
"Only CS$_2$ can form intermolecular dipole-dipole forces.",
"COS has stronger intermolecular forces because it is polar and CS$_2$ is not."
] | |||||||||
Chemistry | Which of the labeled arrows in the diagram above represents the strongest intermolecular force?
| 1 | [
"A",
"B",
"C",
"D"
] | |||||||||
Chemistry | A dimer consists of two closely associated molecules. In the gas phase, acetic acid tends to form dimers as illustrated on the left in the above diagram. Acetyl chloride, on the right in the above diagram, is not very efficient in forming dimers. Why is acetic acid better able to form dimers than acetyl chloride?
| 2 | [
"The molecular mass of acetyl chloride is higher than that of acetic acid making it harder for the acetyl chloride to form dimers.",
"It is easier to form a covalent bond between acetic acid molecules than between acetyl chloride molecules.",
"Acetic acid can form strong hydrogen bonds but acetyl chloride can o... | |||||||||
Chemistry | Which of the compounds in the above diagram is capable of participating in hydrogen bonding?
| 3 | [
"C$_3$H$_9$ N",
"CH$_3$F",
"C$_2$H$_6$O",
"C$_4$H$_11$"
] | |||||||||
Chemistry | In the diagram above, which labeled arrow is pointing toward a hydrogen bond?
| 2 | [
"1",
"2",
"3",
"4"
] | |||||||||
Chemistry | The graph above shows the distribution of kinetic energies of a large number of Ne atoms at 500 K. Which letter shows the average kinetic energy of this system?
| 2 | [
"A",
"B",
"C",
"D"
] | |||||||||
Chemistry | The above graph shows a titration curve of a weak base titrated with a strong acid. The pH was measured with a pH meter after small volumes of 0.075 M HCl were added to 25.0 mL of a weak base. Data from that experiment are shown in the graph. Which arrow points to the end point of this titration?
| 1 | [
"A",
"E",
"C",
"F"
] | |||||||||
Chemistry | The above graph shows a titration curve of a weak base titrated with a strong acid. The pH was measured with a pH meter after small volumes of 0.075 M HCl were added to 25.0 mL of a weak base. Data from that experiment are shown in the graph. Which arrow points to the place on the curve where the pH is equal to 14 - pK... | 2 | [
"A",
"E",
"C",
"F"
] | |||||||||
Chemistry | The Lewis diagram for nitric acid, $HNO_3$, is above. Which of the following statements is true regarding nitric acid?
| 0 | [
"$HNO_3$ molecules are planar.",
"The nitrogen atom carries a negative formal charge.",
"All N-O bonds are of identical length.",
"There is a third equivalence resonance structure that is not shown."
] | |||||||||
Chemistry | The photoelectron below spectrum is for a neutral fluorine atom. Compared to that spectrum, the spectrum for a fluoride ion would have
| 2 | [
"one more peak",
"one less peak",
"the same number of peaks, but the rightmost peak would be taller",
"the same number of peaks, but the leftmost peak would be taller"
] | |||||||||
Chemistry | A student is attempting to use a distillation apparatus, shown below, to separate a mixture of propanol (boiling point: 97°C) and propionic acid (boiling point: 141°C). Which temperature should the apparatus be set at to obtain as pure a distillate of propanol as possible?
| 1 | [
"85°C",
"105°C",
"125°C",
"145°C"
] | |||||||||
Chemistry | Given the half-reactions below, what would the coefficient on the $NO(g)$ be when the full reaction below is balanced?
| 1 | [
"1",
"2",
"3",
"4"
] | |||||||||
Chemistry | A Lewis diagram of the hydrogen phosphate ion is shown below. Based on this diagram, which of the atoms would have a negative formal charge?
| 3 | [
"P",
"Ox",
"Oy",
"Oz"
] | |||||||||
Chemistry | The $K_a$ values for three different weak acids are given below. If the acid is polyprotic, all of the $K_a$ values for that acid are given. If each acid were to be titrated with 0.10 M NaOH, which solution would have the highest pH at the endpoint of the titration when each acid has fully reacted?
| 1 | [
"Formic",
"Sulfurous",
"Citric",
"All titrations would have identical pHs at the endpoint."
] | |||||||||
Chemistry | A piece of potassium metal is added to a solution of hydrochloric acid, and the metal starts to react. Which of the following is the correct net ionic equation for the reaction that is occurring?
| 3 | [
"$2H^+(aq) + K^+(aq) + 3e^- \\rightarrow H_2(g) + K(s)$",
"$2H^+(aq) + 2K^+(aq) + 4e^- \\rightarrow 2K(s) + H_2(g)$",
"$2H^+(aq) + K(s) \\rightarrow K^+(aq) + H_2(g)$",
"$2H^+(aq) + 2K(s) \\rightarrow 2K^+(aq) + H_2(g)$"
] | |||||||||
Chemistry | The Lewis diagram of the bisulfite ion, $HSO^{3-}$, is drawn below. Which of the following descriptions correctly compares the bond lengths of the three sulfur-oxygen bonds found in bisulfite?
| 1 | [
"All bonds are the same length.",
"Of the three bonds, there is one longer one and two shorter ones of identical length.",
"Of the three bonds, there are two longer ones of identical length and one shorter one.",
"All three bonds are different lengths."
] | |||||||||
Chemistry | A sample of hydrogen peroxide, $H_2O_2$, will decompose over time. The graph below charts the concentration of an $H_2O_2$ sample over time. What is the rate law for the overall reaction?
| 1 | [
"Rate = k",
"Rate = k[$H_2O_2$]",
"Rate = k[$H_2O_2$]2",
"Rate = k[$H_2O$][$O_2$]"
] | |||||||||
Chemistry | A semiconductor with a silicon lattice is doped by the addition of another element, symbolized by the letter X in the diagram below. Which of the following statements best describes the possible identity of the element as well as the type of doping that is occurring?
| 0 | [
"Boron, which has less valence electrons than silicon and creates positive \"holes\" in the lattice",
"Phosphorus, which has extra valence electrons and creates a mobile negative charge in the lattice",
"Aluminum, which has metalloid properties that lend to increased conductivity when added to a semiconductor",... | |||||||||
Chemistry | Given the bond enthalpy values in the data table below, determine the enthalpy change for the reaction above it.
| 0 | [
"-1220 kJ/mol",
"-400 kJ/mol",
"400 kJ/mol",
"1220 kJ/mol"
] | |||||||||
Chemistry | $[NO]$ (M) $[O_2]$ (M)
The reaction below is run with the concentration of both reactants at 0.10 M. Which of the following values for the initial concentration of both reactants would lead to an initial reaction rate which is double that of the first trial?
| 2 | [
"0.15 0.15",
"0.20 0.20",
"0.20 0.050",
"0.050 0.20"
] | |||||||||
Chemistry | Two batteries are constructed via the diagram below. The concentration of the solutions and the mass of the electrodes are identified in the data below the diagram. How would the voltage and the battery life for the two batteries compare?Voltage Battery Life
| 3 | [
"X <Y X <Y",
"X <Y X =Y",
"X =Y X = Y",
"X =Y X < Y"
] | |||||||||
Chemistry | $Cu^{2+}$ ions appear blue in solution, and the $NO_3^-$ ion is colorless. The absorbance of a $Cu(NO_3)_2$ solution is measured at various wavelengths using a spectrophotometer. To determine the concentration of a $Cu(NO_3)_2$ solution of unknown concentration, what wavelength of light would produce the best results?
| 2 | [
"350 nm",
"500 nm",
"640 nm",
"800 nm"
] | |||||||||
Chemistry | The diagram below supports which of the following conclusions about the reaction shown below?
| 1 | [
"There is an increase in entropy.",
"Mass is conserved in all chemical reactions.",
"The pressure increases after the reaction goes to completion.",
"The enthalpy value is positive."
] | |||||||||
Chemistry | Ox N Oy
One of the resonance structures for the nitrite ion is shown below. What is the formal charge on each atom?
| 3 | [
"-1 +1 -1",
"+1 -1 0",
"0 0 -1",
"-1 0 0"
] | |||||||||
Chemistry | Identify the three gases represented on the Maxwell-Boltzmann diagram below. Assume all gases are at the same temperature.I II III
| 2 | [
"$H_2$ $N_2$ $F_2$",
"$H_2$ $F_2$ $N_2$",
"$F_2$ $N_2$ $H_2$",
"$N_2$ $F_2$ $H_2$"
] | |||||||||
Chemistry | If the $H_2C_2O_4$ were to be replaced with an identical volume of $H_2SO_4$, what volume of $NaOH$ would be required to fully neutralize the acid?
A 0.10 M solution of $NaOH$ is titrated into 20 mL of $H_2C_2O_4$, a diprotic acid, of an unknown concentration. The pH of the $H_2C_2O_4$ solution is monitored as the $NaO... | 1 | [
"10 mL",
"20 mL",
"40 mL",
"60 mL"
] | |||||||||
Chemistry | 5mL 15mL 25mL
Phenolphthalein is an acid-base indicator with a pKa of 9.1. Its protonated form is often abbreviated as $HIn$, while its conjugate base is abbreviated as $In^-$. At the following volumes of NaOH added, select the option that accurately describes which form of the indicator will be present in... | 0 | [
"$HIn$ $HIn$ $In^-$",
"$HIn$ $In^-$ $In^-$",
"$In^--$ $In^-$ $HIn$",
"$In^-$ $HIn$ $HIn$"
] | |||||||||
Chemistry | At the point at which 20 mL of NaOH has been added, which of the following species is present in the greatest concentration in solution?
A 0.10 M solution of NaOH is titrated into 20 mL of $H_2C_2O_4$, a diprotic acid, of an unknown concentration. The pH of the $H_2C_2O_4$ solution is monitored as the NaOH is added ... | 3 | [
"$H^+$",
"$OH^-$",
"$HC_2O_4^-$",
"$C_2O_4^{2-}$"
] | |||||||||
Chemistry | What is the concentration of the $H_2C_2O_4$ solution?
A 0.10 M solution of NaOH is titrated into 20 mL of $H_2C_2O_4$, a diprotic acid, of an unknown concentration. The pH of the $H_2C_2O_4$ solution is monitored as the NaOH is added to it, resulting in the below graph.
| 1 | [
"0.025 M",
"0.050 M",
"0.10 M",
"0.20 M"
] | |||||||||
Chemistry | Data considering the conductivity of four different substances in their various phases is given in the table below. Of the four options, which substance is most likely to be $NaCl$?
| 1 | [
"Substance A",
"Substance B",
"Substance C",
"Substance D"
] | |||||||||
Chemistry | As shown below, four identical containers hold the same number of moles of four different gases at 298 K. If ideal behavior is NOT assumed, in which container would the pressure be the lowest?
| 0 | [
"$H_2O$",
"$CH_4$",
"$Ne$",
"$He$"
] | |||||||||
Chemistry | Based on the mass spectrum shown below, which of the following can be concluded about zirconium?
| 3 | [
"The most common charge on a zirconium ion is +2.",
"Zirconium nuclei can have different number of protons.",
"The average atomic mass of a zirconium atom is 90 amu.",
"The most common isotope of zirconium has 50 neutrons."
] | |||||||||
Chemistry | The system below is at equilibrium. If it were to be diluted, what would happen to the moles of reactants and the moles product after equilibrium is reestablished?Mole Reactants Moles Product
| 1 | [
"Increase Increase",
"Increase Decrease",
"Decrease Decrease",
"No Change No Change"
] | |||||||||
Chemistry | A sample of some $N_2O_5$ gas is placed in a sealed container and allowed to decompose. The concentration of the $N_2O_5$ is tracked over time, and the results are plotted on the above graph. Which of the following represents the possible units on the rate constant for this reaction?
| 0 | [
"$s^{-1}$",
"$sM^{-1}$",
"$Ms^{-1}$",
"$Ms^{-2}$"
] | |||||||||
Chemistry | Vapor Pressure @ 25°C (torr)
Substance
Three different liquids are mixed together in a flask, and that flask is then hooked up to a distillation apparatus, as shown below. The liquids are initially at 25°C, and the heat is turned up until the mixture starts to boil. Which liquid would be the first to separate out of... | 1 | [
"$H_2O$",
"$CH_3OH$",
"$C_6H_{12}$",
"Distillation would be an ineffective method of separating the mixture."
] | |||||||||
Chemistry | 1.0 mole of $NO_2(g)$ is bubbled through excess water, causing the above reaction to take place. Which of the following statements correctly describes the energy change that will occur during the reaction?
| 1 | [
"135 kJ of energy will be emitted.",
"45 kJ of energy will be emitted.",
"135 kJ of energy will be absorbed.",
"405 kJ of energy will be absorbed."
] | |||||||||
Chemistry | A beaker is filled with some 1.0 M $CuSO_4$, and two carbon electrodes are placed in the beaker with a battery wired between them, as shown below. As current is run through the system, solid copper plates out onto the carbon cathode. Which of the following changes would increase the amount of solid copper that is plate... | 1 | [
"Replacing the 1.0 M $CuSO_4$ solution with 1.0 M $CuCl_2$",
"Using a 9.0 V battery instead of a 1.5 V battery",
"Decreasing the pH of the solution",
"Changing out the carbon electrodes with platinum electrodes"
] | |||||||||
Chemistry | The photoelectron spectrum of an element is below. Based on the spectrum, what is the charge on the most common ion of the element?
| 3 | [
"-2",
"-1",
"+1",
"+2"
] | |||||||||
Chemistry | A beaker of saturated zinc iodate is left out overnight. The following morning, some water is found to have evaporated. Assuming the temperature remained constant at 25°C, which of the following options correctly identifies the changes in the $[Zn^{2+}]$ and the mass of the zinc iodate present in the beaker compared to... | 2 | [
"Increase Decrease",
"Increase No Change",
"No Change Increase",
"No Change Decrease"
] | |||||||||
Chemistry | Zinc iodate dissociates in water via the following equilibrium process. Which of the following solutions would zinc iodate be the LEAST soluble in?
| 1 | [
"1.0 M BaCl2",
"1.0 M NaIO3",
"1.0 M K2CO3",
"Pure water"
] | |||||||||
Chemistry | What is the approximate molar solubility of zinc iodate at 25°C?
Zinc iodate dissociates in water via the following equilibrium process
| 0 | [
"$1.0 \\times 10^{-2}$ M",
"$2.0 \\times 10^{-3}$ M",
"$4.0 \\times 10^{-6}$ M",
"$1.0 \\times 10^{-6}$ M"
] | |||||||||
Chemistry | When the oxidation-reduction reaction below is completely balanced, what is the coefficient on the $MnO_4^-$ ion?
| 1 | [
"1",
"2",
"3",
"4"
] | |||||||||
Chemistry | The mass spectrum below shows the distribution of various isotopes of strontium. Based on the data, which of the following conclusions can be drawn?
| 3 | [
"Strontium most commonly forms ions with a charge of +2.",
"Strontium isotopes with a mass of 86 or 87 are very unstable.",
"The number of protons in a strontium atom nucleus can vary.",
"The most common isotope of strontium has 50 neutrons."
] | |||||||||
Chemistry | The Lewis diagrams for both ethanol and octane are drawn below. Ethanol's boiling point is 78°C, while octane's is 125°C. This is best explained by the fact that
| 2 | [
"octane has hydrogen bonding, while ethanol does not",
"octane has a significantly higher molar mass than ethanol",
"octane's temporary dipoles are stronger than those in ethanol",
"octane is more symmetrical than ethanol"
] | |||||||||
Chemistry | If a small, pinhole-size leak were to be drilled into each container, the container with which gas would experience the fastest pressure decrease?
10.0 g each of three different gases are present in three glass containers of identical volume, as shown below. The temperature of all three flasks is held constant at 298 K... | 1 | [
"$SO_2$",
"$CH_4$",
"$NCl_3$",
"All three containers would decrease pressure at the same rate."
] | |||||||||
Chemistry | 10.0 g each of three different gases are present in three glass containers of identical volume, as shown below. The temperature of all three flasks is held constant at 298 K.Which of the gases would have the greatest density?
| 3 | [
"$SO_2$",
"$CH_4$",
"$NCl_3$",
"All three gases would have the same density."
] | |||||||||
Chemistry | The container with which gas would have the greatest pressure?
10.0 g each of three different gases are present in three glass containers of identical volume, as shown below. The temperature of all three flasks is held constant at 298 K.
| 1 | [
"$SO_2$",
"$CH_4$",
"$NCl_3$",
"All four containers would have the same pressure."
] | |||||||||
Chemistry | $SiCl_4$ $PCl_3$
The Lewis diagrams for $SiCl_4$ and $PCl_3$ are drawn below. What are the approximate bond angles between the terminal chlorine atoms in each structure?
| 1 | [
"90 90",
"109.5° < 109.5°",
"90° 109.5°",
"< 109.5° > 90°"
] | |||||||||
Chemistry | X Y Z
The formate ion, $HCO_2^-$, is best represented by the Lewis diagram below. Each bond is labeled with a different letter.What is the bond order for each bond?
| 2 | [
"1 1 2",
"2 2 1",
"1 1.5 1.5",
"1.33 1.33 1.33"
] | |||||||||
Chemistry | Initial pH Equivalence pH Ending pH
A student titrates some 1.0 M $HCl$ into 20.0 mL of methylamine ($CH_3NH_2$), a weak base which only accepts a single proton. The following titration curve results:The methylamine is replaced by 20.0 mL of sodium hydroxide of an identical concentration. If the sodium hydrox... | 1 | [
"lower same higher",
"higher higher same",
"same higher same",
"higher lower lower"
] | |||||||||
Chemistry | The buffer region of this titration is located
A student titrates some 1.0 M $HCl$ into 20.0 mL of methylamine ($CH_3NH_2$), a weak base which only accepts a single proton. The following titration curve results:
| 1 | [
"below 3.0 mL",
"between 3.0 mL and 14.0 mL",
"between 14.0 mL and 16.0 mL",
"above 16.0 mL"
] | |||||||||
Chemistry | What is the approximate $pK_b$ for methylamine?
A student titrates some 1.0 M HCl into 20.0 mL of methylamine ($CH_3NH_2$), a weak base which only accepts a single proton. The following titration curve results:
| 0 | [
"3.5",
"5.5",
"10.5",
"12.5"
] | |||||||||
Chemistry | What is the concentration of the methylamine?
A student titrates some 1.0 M HCl into 20.0 mL of methylamine ($CH_3NH_2$), a weak base which only accepts a single proton. The following titration curve results:
| 1 | [
"0.50 M",
"0.75 M",
"1.0 M",
"1.25 M"
] | |||||||||
Chemistry | Silver sulfate, $Ag_2SO_4$, has a solubility product constant of $1.0 \times 10^{-5}$. The below diagram shows the products of a precipitation reaction in which some silver sulfate was formed.Which ion concentrations below would have led the precipitate to form?
| 1 | [
"$[Ag^+] = 0.01 M$ $[SO_4^{2-}] = 0.01 M$",
"$[Ag^+] = 0.10 M$ $[SO_4^{2-}] = 0.01 M$",
"$[Ag^+] = 0.01 M$ $[SO_4^{2-}] = 0.10 M$",
"This is impossible to determine without knowing the total volume of the solution."
] | |||||||||
Chemistry | Silver sulfate, $Ag_2SO_4$, has a solubility product constant of $1.0 \times 10^{-5}$. The below diagram shows the products of a precipitation reaction in which some silver sulfate was formed.If the beaker above were left uncovered for several hours
| 3 | [
"some of the $Ag_2SO_4$ would dissolve",
"some of the spectator ions would evaporate into the atmosphere",
"the solution would become electrically imbalanced",
"additional $Ag_2SO_4$ would precipitate"
] | |||||||||
Chemistry | Silver sulfate, $Ag_2SO_4$, has a solubility product constant of $1.0 \times 10^{-5}$. The below diagram shows the products of a precipitation reaction in which some silver sulfate was formed.What is the identity of the excess reactant?
| 0 | [
"$AgNO_3$",
"$Ag_2SO_4$",
"$NaNO_3$",
"$Na_2SO_4$"
] | |||||||||
Chemistry | The following curve is obtained during the titration of 30.0 mL of 1.0 M $NH_3$, a weak base, with a strong acid:What ions are present in significant amounts during the first buffer region?
| 0 | [
"$NH_3$ and $NH_4^+$",
"$NH_3$ and $H^+$",
"$NH_4^+$ and $OH^-$",
"$H_3O^+$ and $NH_3$"
] | |||||||||
Chemistry | The following curve is obtained during the titration of 30.0 mL of 1.0 M NH3, a weak base, with a strong acid:What is the concentration of the acid?
| 3 | [
"0.5 M",
"1.0 M",
"1.5 M",
"2.0 M"
] | |||||||||
Chemistry | Why is the solution acidic at equilibrium?
The following curve is obtained during the titration of 30.0 mL of 1.0 M NH3, a weak base, with a strong acid:
| 1 | [
"The strong acid dissociates fully, leaving excess $[H^+]$ in solution.",
"The conjugate acid of NH3 is the only ion present at equilibrium.",
"The water which is being created during the titration acts as an acid.",
"The acid is diprotic, donating two protons for every unit dissociated."
] | |||||||||
Chemistry | The diagram below shows three identical 1.0 L containers filled with the indicated amounts of gas. The stopcocks connecting the containers are originally closed and the gases are all at 25°C. Assume ideal behavior.The stopcocks are opened. If the tubing connecting the containers has negligible volume, by what percentag... | 3 | [
"25%",
"33%",
"50%",
"67%"
] | |||||||||
Chemistry | The diagram below shows three identical 1.0 L containers filled with the indicated amounts of gas. The stopcocks connecting the containers are originally closed and the gases are all at 25°C. Assume ideal behavior.Which gas has the strongest IMFs?
| 3 | [
"He",
"Ne",
"NO",
"All gases have identical IMFs."
] | |||||||||
Chemistry | The diagram below shows three identical 1.0 L containers filled with the indicated amounts of gas. The stopcocks connecting the containers are originally closed and the gases are all at 25°C. Assume ideal behavior. Which gas exerts the greatest pressure?
| 0 | [
"He",
"Ne",
"NO",
"All gases exert the same amount of pressure."
] | |||||||||
Chemistry | Which structure is more likely to correspond with the actual Lewis diagram for the sulfate ion?
There are several different potential Lewis diagrams for the sulfate ion, two of which are below.
| 3 | [
"Structure A; single bonds are more stable than double bonds",
"Structure A; it has the most unshared pairs of electrons",
"Structure B; there are more possible resonance structures",
"Structure B; fewer atoms have formal charges"
] | |||||||||
Chemistry | Which of the following statements regarding the structure B is true?
There are several different potential Lewis diagrams for the sulfate ion, two of which are below.
| 3 | [
"The double bonds must be located opposite of each other due to additional electron repulsion.",
"It is a more polar molecule than the molecule represented by structure A.",
"The bonds in the molecule are weaker than those in structure A.",
"All bonds in the molecule are identical to each other."
] | |||||||||
Chemistry | What is the S-O bond order in the structure B?
There are several different potential Lewis diagrams for the sulfate ion, two of which are below.
| 2 | [
"1.0",
"1.33",
"1.5",
"1.67"
] | |||||||||
Chemistry | What is the molecular geometry in the structure A?
There are several different potential Lewis diagrams for the sulfate ion, two of which are below.
| 0 | [
"Tetrahedral",
"Trigonal Planar",
"Trigonal Pyramidal",
"Octahedral"
] | |||||||||
Chemistry | Use the PES spectra below to answer questions.How many valence electrons does this atom have?
| 3 | [
"2",
"3",
"4",
"5"
] | |||||||||
Chemistry | An electron from which peak would have the greatest velocity after ejection?
Use the PES spectra below to answer questions.
| 3 | [
"The peak at 104 MJ/mol",
"The peak at 6.84 MJ/mol",
"The peak at 4.98 MJ/mol",
"The peak at 1.76 MJ/mol"
] | |||||||||
Chemistry | How many significant digits are present in the temperature read from the thermometer illustrated to the right?
| 2 | [
"1",
"2",
"3",
"4"
] | |||||||||
Chemistry | The marks on the following target represent someone who is:
| 3 | [
"accurate, but not precise.",
"precise, but not accurate.",
"both accurate and precise.",
"neither accurate nor precise."
] | |||||||||
Chemistry | Pictured below is a schematic of the Rutherford experiment. Which scattered -particle gives the best evidence for the nuclear atom?
| 0 | [
"a",
"b",
"c",
"d"
] | |||||||||
Chemistry | What position on the standing wave shown below corresponds to a crest?
| 1 | [
"a",
"b",
"c",
"d",
"e"
] | |||||||||
Chemistry | The value of l that is related to the following orbital is:
| 1 | [
"0",
"1",
"2",
"3",
"4"
] | |||||||||
Chemistry | The titration curves labeled 1 and 2 were obtained by titrating equal volumes of two different acid samples with portions of the same sodium hydroxide solution. What conclusions can be drawn about the relative concentrations and strengths of acids 1 and 2 from these curves?
| 0 | [
"The concentrations are the same but acid 1 is weaker than acid 2.",
"The concentrations are the same but acid 1 is stronger than acid 2.",
"Acid 1 is the same strength as acid 2, but it is less concentrated.",
"Acid 1 is the same strength as acid 2, but it is more concentrated."
] | |||||||||
Chemistry | According to the above data, what is the half-life of the substance?
| 2 | [
"1.0 hrs",
"2.3 hrs",
"3.0 hrs",
"8.0 hrs"
] | |||||||||
Chemistry | What percent of the original sample remains after 4 hours?
| 3 | [
"80%",
"75%",
"60%",
"40%"
] | |||||||||
Chemistry | The elements I and Te have similar average atomic masses. A sample that was believed to be a mixture of I and Te was run through a mass spectrometer which separates a sample by mass into isotopes, resulting in the data below. All of the following statements are true. Which one would be the best basis for concluding tha... | 2 | [
"Te forms ions with a -2 charge, whereas I forms ions with a -1 charge.",
"Te is more abundant than I in the universe.",
"I consists of only one naturally occurring isotope with 74 neutrons, whereas Te has more than one isotope",
"I has a higher first ionization energy than Te does."
] | |||||||||
Chemistry | The diagram below models a change that occurs in matter. Based on what you know about changes in matter, explain why the diagram shows a physical change rather than a chemical change.
| 2 | [
"The particles get smaller.",
"The volume of the matter decreases.",
"The composition of the matter stays the same.",
"The particles change into particles of different substances"
] | |||||||||
Chemistry | In an experiment, a solid 1 molar sample of Substance A was gradually heated by a source of constant energy for several hours and the temperature was measured periodically. At the end of the heating period, Substance A had been converted to the gas phase. The heating curve produced by this experiment is shown below. Du... | 1 | [
"Between 100 K and 150 K",
"At 150 K",
"Between 150 K and 250 K",
"At 250 K",
"Between 250 K and 350 K"
] | |||||||||
Chemistry | In an experiment, a solid 1 molar sample of Substance A was gradually heated by a source of constant energy for several hours and the temperature was measured periodically. At the end of the heating period, Substance A had been converted to the gas phase. The heating curve produced by this experiment is shown below. Ba... | 3 | [
"The boiling point of Substance A is 250 K.",
"The freezing point of Substance A is150 K.",
"The heat of vaporization of Substance A is greater than the heat of fusion.",
"Substance A is a liquid at room temperature.",
"The intermolecular forces exhibited by Substan"
] | |||||||||
Chemistry | In an experiment, a solid 1 molar sample of Substance A was gradually heated by a source of constant energy for several hours and the temperature was measured periodically. At the end of the heating period, Substance A had been converted to the gas phase. The heating curve produced by this experiment is shown below. Du... | 0 | [
"was used to change from liquid to gas phase.",
"was used to change from gas to liquid phase.",
"was used to change from solid to liquid phase.",
"was used to change from liquid to solid phase.",
"was reduced to zero."
] | |||||||||
Chemistry | Which of the following is true of the reactions shown in the diagram above?
| 2 | [
"The reaction is endothermic because the reactants are at a higher energy level than the products.",
"The reaction is endothermic because the reactants are at a lower energy level than the products.",
"The reaction is exothermic because the reactants are at a higher energy level than the products.",
"The reac... | |||||||||
Chemistry | Which point on the graph shown above corresponds to an activated complex or transition state?
| 2 | [
"1",
"2",
"3",
"4",
"5"
] | |||||||||
Chemistry | The following titration curve shows the titration of a weak base with a strong acid. Which of the following values most accurately approximates the p$K_b$ of the weak base?
| 4 | [
"9.8",
"8.4",
"7",
"3.3",
"4.2"
] | |||||||||
Chemistry | Given a reaction A+B →C. Based on the following experimental data, what is the rate law for the hypothetical reaction given above?
| 2 | [
"Rate= $k[A]$",
"Rate= $k[A]^2$",
"Rate = $k[B]$",
"Rate = $k[B]^2$",
"Rate = $k[A][B]$"
] | |||||||||
Chemistry | Given a reaction A+B →C. Based on the following experimental data, what is the rate law for the hypothetical reaction given above?
| 4 | [
"Rate= $k[A]$",
"Rate= $k[A]^2$",
"Rate = $k[B]$",
"Rate = $k[B]^2$",
"Rate = $k[A][B]$"
] | |||||||||
Chemistry | Given a reaction A+B →C. Based on the following experimental data, what is the rate law for the hypothetical reaction given above?
| 2 | [
"Rate= $k[A][B]$",
"Rate= $k[A]^2$",
"Rate = $k[A][B]^2$",
"Rate = $k[B]^2$",
"Rate = $k[A]^2[B]^2$"
] | |||||||||
Chemistry | The formal charge on carbon in the molecule below is.
| 0 | [
"0",
"+1",
"-1",
"+3",
"+2"
] |
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