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Straighterline Chemistry Final Exam
_____ is a trend that describes ligands from strong field to weak field. Electronegativity The spectrochemical series The crystal field model - ANSWER-The spectrochemical series 77 K is colder than 4 K. Select one: True False - ANSWER-False A cation has a ______ charge. - ANSWER-positive A CH3COOH/CH3COO- buffer can be produced by adding a strong acid to a solution of CH3COO- ions. Select one: True False - ANSWER-True A complex ion that undergoes a very slow exchange reaction is called an inert complex. Select one: True False - ANSWER-True A concentration term commonly used for solutions that uses the volume of a solution is ______. - ANSWER-Molarity A coordination environment where a metal is surrounded by six ligands is called _______. Linear Tetrahedral Octahedral - ANSWER-Octahedral A face-centered crystal lattice has one atom in the center of the unit cell. Select one: True False - ANSWER-False
A hydrohalic acid is a binary acid containing a halogen. Select one: True False - ANSWER-True A ligand that forms one bond to the metal is called a(n) _________. Ionic bond Unidentate Covalent bond - ANSWER-Unidentate A nuclear reaction's reaction rate is affected by temperature, pressure, and catalysts. Select one: True False - ANSWER-False A particular temperature in degrees Celsius is larger than the temperature in kelvins. Select one: True False - ANSWER-False A phase diagram is a diagram depicting the phases of a substance at different temperatures and pressures. True False - ANSWER-True A reaction in which the same element gains and loses electrons is known as a(n) ________ reaction. Acid-base Dissolution Disproportionation - ANSWER-Disproportionation A reaction where electrons are transferred from one reactant to another is called a(n) __________ reaction. Redox or oxidation-reduction Acid-base Ionic - ANSWER-Redox or oxidation-reduction A reduction in atomic radii caused by the 4f electrons being close to the nucleus is called ______.
According to the VSEPR model, a molecule with the general formula AB5 with one lone pair on the central atom will have a ______ molecular geometry. Select one: a. tetrahedral b. trigonalbipyramidal c. square pyramidal d. octahedral e. seesaw - ANSWER-c. square pyramidal According to the VSEPR model, the predicted molecular geometry of ammonia, NH3, is Select one: a. linear. b. trigonal planar. c. bent. d. tetrahedral. e. trigonal pyramidal. - ANSWER-e. trigonal pyramidal. Acetic acid is a very important industrial chemical and is produced by this reaction: CH3OH(l) + CO(g) à CH3COOH(l) Calculate the value of the standard Gibbs Free Energy change for this reaction. Is acetic acid thermodynamically stable compared with liquid water at standard conditions? Explain. Compound Standard Gibbs Free Energy (kJ/mol) H2O (l) -237. CH3COOH -389. CH3OH (I) -166. CO (g) -137.
A. ΔG°rxn = -86.0 kJ; At standard conditions, acetic acid is less thermodynamically stable than water because it has a more negative value of ΔG°. B. ΔG°rxn = -86.0 kJ; At standard conditions, acetic acid is more thermodynamically stable than water because it has a more negative value of ΔG°. C. ΔG°rxn = +86.0 kJ; At standard conditions, acetic acid is less thermodynamically stable than water because it has a more negative value of ΔG°. D.. ΔG°rxn = -0.017 kJ; At standard conditions, acetic acid is less t - ANSWER-A. ΔG°rxn = -86.0 kJ; At standard conditions, acetic acid is less thermodynamically stable than water because it has a more negative value of ΔG°. Acetylene (properly known as ethyne) and calcium hydroxide are the products of the reaction between calcium carbide (CaC2) and water. Ethyne can be easily set on fire. This can be done on the surface of an ice cube, giving it the appearance of "burning ice". Identify the balanced reaction for the combustion of ethyne and explain why it burns with intense heat. A. 2C2H2 + 5O2 à 4CO2 + 2H2O; There is a lot of energy released in this reaction because there is a triple bond between the carbons in ethyne, which contains a lot of energy, and this energy is released when the bonds are broken. B. C2H4 + 3O2 à 2CO2 + 2H2O; There is a lot of energy released in this reaction because there is a double bond between the carbons in ethyne, which contains a lot of energy, and this energy is released when the bonds are broken. C. C2H4 + 3O2 à 2CO2 + 2H2O; There is a lot of energy released in this reaction because the energy releas - ANSWER-D. 2C2H2 + 5O2 à 4CO2 + 2H2O; There is a lot of energy released in this reaction because the energy released when forming the chemical bonds in four moles of CO2 and two moles of water H2O is much more than the energy required to break the chemical bonds in two moles of ethyne and five moles of oxygen. Acid-base reactions are also called ________ reactions. Neutralization Ionic Dipole - ANSWER-Neutralization Acid-base reactions are also called - ANSWER-neutralization reactions Acids are compounds that dissolve in water to produce - ANSWER-protons All elements fall into one of the following groups: - ANSWER-metal, nonmetal, metalloid
An alloy is an example of a _______ solution. - ANSWER-solid-solid An anion has a _____ charge. - ANSWER-negative An element with the general electron configuration for its outermost electrons of ns2np would be in which element group? Select one: a. 2A b. 3A c. 4A d. 5A e. 8A - ANSWER-b. 3A An emulsion is a dispersion consisting of a Select one: a. solid in a liquid. b. liquid in a liquid. c. gas in a liquid. d. liquid in a solid. e. gas in a solid. - ANSWER-b. liquid in a liquid. Arrhenius - ANSWER-Defined acids as proton donors and bases as hydroxide donors As the molar mass of a compound increases, the entropy ______. Select one: a. decreases b. is constant c. increases - ANSWER-c. increases Atomic number = - ANSWER-protons Atomic size decreases across a period due to an increase in the effective nuclear charge, Zeff. Select one: True False - ANSWER-True Atoms that have the same number of protons but different numbers of neutrons are called - ANSWER-Isotopes Avogardro's number represents - ANSWER-atoms Bases are compounds that dissolve in water to produce - ANSWER-hydroxide ions
Beta rays - ANSWER-Electrons that are deflected away from the negatively charged plate Boiling point elevation - ANSWER-the difference in temperature between the boiling point of a solution and the boiling point of the pure solvent Boiling point elevation is a colligative property that involves the increase in the boiling point of a solvent by the addition of a solute - ANSWER-True Boyle's Law - ANSWER-A principle that describes the relationship between the pressure and volume of a gas at constant temperature Boyle's law is a gas law that associates the product of the pressure and volume with the number of moles, temperature, and a universal proportionality constant. - ANSWER- True Bromination of benzene (C6H6), an aromatic compound, Select one: a. occurs by substitution rather than addition. b. occurs by addition rather than substitution. c. occurs more rapidly than bromination of a nonaromatic compound. d. results in the formation of 1,2,3,4,5,6-hexabromocyclohexane. e. occurs in the absence of a catalyst. - ANSWER-a. occurs by substitution rather than addition. C(graphite) and C(diamond) are examples of: Select one: a. isotopes of carbon. b. allotropes of carbon. c. the law of definite proportions. d. different carbon ions. - ANSWER-b. allotropes of carbon. Calculate Ecell for the galvanic cell based on these half-reactions at 25oC, in which [H2SO4] = 0.5 M HSO4- (aq) + Pb (s) H+ (aq) + PbSO4 (s) + 2 e- Eo = +0.35 V PbO2 (s) + 3H+ (aq) + HSO4- (aq) + 2 e- PbSO4 (s) + 2H2O (l) Eo = +1.46 V If the concentration of sufuric acid is increased, will Ecell increase or decrease? Explain. A. This question cannot be answered with the information given. Concentrations of the other reactants and products are necessary.
Discovered the nucleus - ANSWER-Ernest Rutherford E. Rutherford is credited with discovering the - ANSWER-Nucleus Effusion - ANSWER-Transfer of gas through a small orifice into an evacuated chamber Effusion is the transfer of gas through a small orifice into an evacuated chamber. - ANSWER-True Element essential for plant growth - ANSWER-potassium Element- = - ANSWER-plus one electron Element+ = - ANSWER-Minus one electron Elements in which the outermost electron has the same principal quantum number, n, show similar chemical properties. Select one: True False - ANSWER-False Emission spectra Select one: a. cannot be used to identify an unknown atom. b. can be used to identify unknown atoms. c. can be explained by the movement of protons colliding with electrons. d. none of the. - ANSWER-b. can be used to identify unknown atoms. Emission Spectrum - ANSWER-radiation that is emitted by atoms Empirical Formula - ANSWER-a formula with the lowest whole-number ratio of elements in a compound Ernest Rutherford disproved J.J. Thomson's plum-pudding model of the atom by showing that a. atoms are, in fact, not electrically neutral. b. the atom contains neutrons. c. positive matter is concentrated in the central core. d. electrons are actually greater in mass than protons. - ANSWER-c. positive matter is concentrated in the central core. Ernest Rutherford disproved JJ Thomson's plum-pudding model by showing that - ANSWER-positive matter is concentrated in the central core
Ethanol (C2H5-OH) will have a greater viscosity than ethylene glycol (HO-CH2CH2-OH) at the same temperature. Select one: True False - ANSWER-False Ethylenediaminetetraacetic acid (EDTA) is Select one: a. not useful as a chelating agent. b. an effective antidote for heavy metal poisoning (e.g., Pb2+ and Hg2+). c. a monodentate ligand. d. known to form unstable complex ions with Fe3+, Hg2+, and Zn2+. e. known to form complexes with platinum that inhibit the growth of cancerous cells. - ANSWER-b. an effective antidote for heavy metal poisoning (e.g., Pb2+ and Hg2+). For a conjugate acid-base pair, Kw = Ka/Kb Select one: True False - ANSWER-False For a gas obeying Boyle's law, a plot of V versus 1/P will give a straight line passing through the origin. Select one: True False - ANSWER-False For real gases, PV > nRT. Select one: True False - ANSWER-False For stable atoms of elements having low atomic numbers (≤ 20), the neutron-to-proton ratio is close to zero. Select one: True False - ANSWER-False For which one of the following molecules is the indicated type of hybridization not appropriate for the central atom? Select one:
a. Atomic radius decreases moving from left to right across a period and increases from top to bottom. b. Atomic radius increases moving left to right across a period and decreases from top to bottom. c. Smaller nuclear charge lowers energy; more electrons in an orbital lowers energy. d. Atomic radius increases diagonally across the periodic table. e. None of the answers is correct. - ANSWER-a. Atomic radius decreases moving from left to right across a period and increases from top to bottom. How is the mass number of an element different from its atomic number? Select one: a. The mass number represents the total number of protons in one atom of the element as opposed to the total number of neutrons. b. The mass number represents the total number of electrons in one atom of the element as opposed to the total number of protons. c. The mass number represents the total number of neutrons and protons in one atom of the element as opposed to the total number of protons. d. The mass number represents the total number of neutrons and electrons in one atom of the element as opposed to the total number of neutrons. - ANSWER-c. The mass number represents the total number of neutrons and protons in one atom of the element as opposed to the total number of protons How many micrograms are in 65.3 kg? Select one: a. 0.653 μg b. 6.53 × 107 μg c. 6.53 × 104 μg d. 6.53 × 10-8 μg e. 6.53 × 1010 μg - ANSWER-e. 6.53 × 1010 μg How many neutrons are there in an atom of lead whose mass number is 208? Select one: a. 82 b. 126 c. 208 d. 290 e. none of them - ANSWER-b. 126 Ice is less dense than water due to the formation of hydrogen bonds. Select one: True False - ANSWER-True
If a cation and anion have different values in their charge, what do you do for the formula? - ANSWER-Swap the charge numbers and put them as subscripts. If a liquid contains 60% sugar and 40% water throughout its composition then what is it called? Select one: a. Solute b. Compound c. Homogeneous mixture d. Heterogeneous mixture e. Solvent - ANSWER-c. Homogeneous mixture If a strong acid such as HCl is diluted sufficiently with water, the pH will be higher than
Select one: True False - ANSWER-False If liquid bromine is cooled to form a solid, which type of solid does it form? Select one: a. atomic b. metallic c. molecular d. ionic e. covalent - ANSWER-c. molecular If the atmospheric pressure in Denver is 0.8800 atm, what is this pressure expressed in mmHg? (1 atm = 101,325 Pa = 760 torr, 1 torr = 1 mmHg)? Select one: a. 151.5 mmHg b. 1.16 × 10-3 mmHg c. 863.6 mmHg d. 8.92 × 104 mmHg e. 668.8 mmHg - ANSWER-e. 668.8 mmHg If the pH of a buffer solution is greater than the pKa value of the buffer acid, the buffer will have more capacity to neutralize added base than added acid. Select one: True False - ANSWER-False In a chemical reaction, the reactant that is used up first is the ___________. - ANSWER-Limiting reagent
D. This would enhance the enzyme's activity, slowing it down. No, this would not be biologically useful because it - ANSWER-C. This would inhibit the enzyme's activity, slowing it down. Yes, this could be biologically useful because it could prevent over- production of the product. In the complex ion [Co(en)2Br2]+, what is the oxidation number of Co? Select one: a. + b. + c. + d. - e. -1 - ANSWER-c. + In the coordination compound [Pt(NH3)2Cl2], the coordination number and oxidation number of the central atom are_____ and _____, respectively. Select one: a. 2; 0 b. 4; + c. 5; 0 d. 4; + e. 6; +2 - ANSWER-d. 4; + In the Lewis structure of the iodate ion, IO3-, that satisfies the octet rule, the formal charge on the central iodine atom is Select one: a. 2. b. 1. c. 0. d. -1. e. -2. - ANSWER-a. 2. In the van der Waals equation, the constant a is a constant that is part of a correction factor for _________. Select one: a. the volume of the gas b. the temperature of the gas c. the pressure of the gas d. the ideal gas constant - ANSWER-c. the pressure of the gas In the van der Waals equation, the constant b is a constant that is part of a correction factor for _________. Select one: a. the volume of the gas b. the temperature of the gas
c. the pressure of the gas d. the ideal gas constant - ANSWER-a. the volume of the gas In which of the following species does the central atom violate the octet rule? Select one: a. CH b. SF c. PCl4+ d. CCl3+ e. NH3 - ANSWER-b. SF In which type of isomerism is there restricted rotation around a bond? Select one: a. Stereoisomers b. Geometrical isomers c. Constitutional isomers d. Conformational isomers e. Connectivity isomers - ANSWER-b. Geometrical isomers Increasing the concentrations of the components of a buffer solution will increase the buffer capacity. Select one: True False - ANSWER-True Increasing the concentrations of the components of a buffer solution will increase the buffer range. Select one: True False - ANSWER-False Indicators are weak acids that are one color in acidic solution and another color in basic solution. Select one: True False - ANSWER-True Ionic compounds tend to form between metals and nonmetals when electrons are transferred from an element with high ionization energy (metal) to an element with a low electron affinity (nonmetal). Select one:
limiting reagent - ANSWER-any reactant that is used up first in a chemical reaction; it determines the amount of product that can be formed in the reaction Many compounds can be represented with the same empirical formula. Select one: True False - ANSWER-False mass number = - ANSWER-number of protons + number of neutrons Mass number = - ANSWER-protons + neutrons Mass number vs. atomic number - ANSWER-mass number represents the total number of neutrons and protons in one atom of the element; atomic number represents the total number of protons. Mass of Electron - ANSWER-charge/(charge/mass) Matter is anything that has mass and occupies space. Select one: True False - ANSWER-True Meniscus - ANSWER-Curved surface of liquid Metals and non-metals are separated in the periodic table by a(n) - ANSWER-Staircase Methyl red is a common acid-base indicator. It has a Ka equal to 6.3 × 10-6. Its un- ionized form is red and its anionic form is yellow. What color would a methyl red solution have at pH = 7.8? Select one: a. green b. red c. blue d. yellow e. violet - ANSWER-d. yellow Molarity - ANSWER-concentration of a solution molecular formula - ANSWER-The chemical formula of a compound determined by its molecular mass Mono = - ANSWER-
Moseley's measurements of nuclear charges of the elements provided the basis for arranging the elements of the periodic table in order of increasing atomic number. Select one: True False - ANSWER-True Most nonmetallic elements are found in which block of the periodic table of elements? Select one: a. s b. p c. d d. f - ANSWER-b. p Node - ANSWER-Point in wavefunction where the electron cannot be found Nuclear fission is the process in which a heavy nucleus (mass number > 200) divides to form smaller nuclei of intermediate mass and one or more protons. Select one: True False - ANSWER-False Number of known elements - ANSWER-118, 94 natural On the periodic table, what is the number above the element? - ANSWER-Atomic Number On the periodic table, what is the number below the element? - ANSWER-Atomic Weight Once the following equation is balanced with the smallest set of whole number coefficients, what is the sum of the coefficients? (Don't forget to include coefficients of one.) __ SF4 + __ H2O → __ H2SO3 + __ HF Select one: a. 4 b. 6 c. 7 d. 9 e. None of these answers is correct. - ANSWER-d. 9 Only valence electrons are shown in the Lewis structure held together by covalent bonds.
