CHEM 105 iClicker Quiz
What is the combined weight of 1 mol of H atoms plus 1 mol of Li atoms?
7.949 g
The heat of formation of ethene (C₂H₄) is 52 kJ/mol, and that of ethane (C₂H₆) is -84 kJ/mol. What is the ΔHº for the balanced hydrogenation reaction: C₂H₄ + H₂ = C₂H₆ a) -136 kJ b) 136 kJ c) 32 kJ d) -32 kJ
a) -136 kJ
A solution is made by dissolving 1.0 g of methanol (MW=32 g/mol) in 1.0 L of water. The concentration of the methanol in mole fraction is approximately a) 0.00056 b) 1.0 c) ½ d) 1.0 x 10² e) 1.0 x 10³
a) 0.00056
If the partial pressure of nitrogen in a gas mixture in a 22.4-L balloon at STP is 76 mm Hg, what is the mole fraction of nitrogen in the mixture? a) 0.1 b) 76 c) 0.5 d) 0.2
a) 0.1
How many nitrate ions are found in 500 mL of a 0.1 M solution of magnesium nitrate? a) 0.1 mol b) 0.2 mol c) 0.5 mol d) 1 mol
a) 0.1 mol
A solution is made by dissolving 1.0 g of methanol in 1.0 L of water. The concentration of the methanol in wt % is approximately a) 0.10 % b) 1.0 % c) 10. % d) 1.0 x 10² % e) 1.0 x 10³ %
a) 0.10 %
At minimum, how many electrons does the standing waveform of a p-orbital represent? a) 1 b) 2 c) 3 d) 4 e) any number
a) 1
The temperature outside today is 50 ºF, which is __________ ºC. a) 10 b) 7 c) 5 d) 21
a) 10
What is the pOH of a 0.001 M solution of hydrochloric acid? a) 11 b) 3 c) -1 d) -11
a) 11
What is the formula weight of calcium sulfate in g/mol? a) 136 b) 36 c) 272 d) 4
a) 136
What is the theoretical yield of water from the incomplete combustion of 8 g of methane? 2CH₄ + 3O₂ → 2CO + 4H₂O a) 18 g b) 9 g c) 36 g d) 2.5 mol e) 3 mol
a) 18 g
If I mix 16 g of oxygen gas with 4 g of helium gas and the total pressure is 3 atm, what is the partial pressure of helium? a) 2 atm b) 1 atm c) 0.5 atm d) 76 mm Hg
a) 2 atm
What volume does 1 mole of an ideal gas occupy at STP? a) 22.4 L b) 11.2 L c) 44.8 L d) 4.7 L
a) 22.4 L
In this room, what is the ratio of the average speed of a He atom to that of an oxygen molecule? (without a calculator) a) 2√2:1 b) 8:1 c) 1:1
a) 2√2:1
What is the weight % of C in lithium acetate? (Formula weight = 66 g/mol) a) 36% b) 24% c) 47%
a) 36%
The pOH of pure water is a) 7 b) -7 c) 14 d) -14 e) 0
a) 7
In the reaction, how many grams of oxygen gas must react with zinc metal to produce 40.7 g of zinc(II) oxide? (zinc is Zn) Zn + O₂ → ZnO a) 8 b) 16 c) 24 d) 32 e) 64
a) 8
How many sigma bonds are in one glycine zwitterion? a) 9 b) 7 c) 5 d) 21
a) 9
a) Blue has a greater amplitude and frequency than Red b) Blue has a greater amplitude and wavelength than Red c) The national debt will be paid off in your lifetime.
a) Blue has a greater amplitude and
For the reaction CaC₂ + 2H₂O → Ca(OH)₂ + C₂H₂ if I start with 18 g of water (FW=18 g/mol) and have a theoretical yield of 10 g of C₂H₂ (MW= 26 g/mol) , the limiting reactant must be a) CaC₂ b) H₂O c) C₂H₂
a) CaC₂
It is experimentally determined that a compound consisting only of C and H is 14% by weight H. If the molecular weight is found to be 28 g/mol, what is the molecular formula? a) C₂H₄ b) C₂H₆ c) C₃H₆ d) C₄H₆
a) C₂H₄
The conjugate base of sulfuric acid H₂SO₄ is a) HSO₄⁻ b) NaOH c) SO₄²⁻ d) HSO₄²⁻ e) H₃SO₄⁺
a) HSO₄⁻
What gas would most closely approach ideality? a) He b) Xe c) CO₂ d) H₂O
a) He
The sigma bond in Cl2 is formed by the overlap of a) a p orbital on Cl and a p orbital on Cl b) an s orbital on Cl and a p orbital on Cl c) an s orbital on Cl and an s orbital on Cl
a) a p orbital on Cl and a p orbital on Cl
Which solute is almost sure to be an electrolyte? (hint: the solvent is water) a) a soluble ionic compound b) a soluble covalent compound c) pure water
a) a soluble ionic compound
Which species contains the shortest C-O covalent bond? a) carbon monoxide b) carbon dioxide c) dioxygen d) dihydrogen
a) carbon monoxide
Choose the species with the highest (largest in magnitude) bond energy (enthalpy) a) cyanide ion b) dioxygen c) methane d) carbon dioxide
a) cyanide ion
The pressure of a gas varies a) directly as the number of molecules b) inversely as the number of molecules c) directly as the radius of the molecules d) inversely as the square of the number of molecules
a) directly as the number of molecules
A covalent bond consists of a) electrons shared between atoms b) electrons transferred from one atom to another c) valence electrons stuck together to form superelectrons
a) electrons shared between atoms
The heat of vaporization of CF₂Cl₂ (Freon-12) is 167 kJ/kg. This heat is a) endothermic b) exothermic
a) endothermic
When an atom forms a cation, it a) gets smaller b) gets larger c) stays the same size d) always loses one or more core electrons e) both a and d
a) gets smaller
In an oxidation process, the oxidation state of an element a) goes up and the element loses electrons b) goes up and the element gains electrons c) goes down and the element loses electrons d) goes down and the element gains electrons
a) goes up and the element loses electrons
Pick the molecule or ion with the largest bond angle a) hydronium ion b) water
a) hydronium ion
If the V of a balloon doubles but the T and number of molecules stays the same, the P of gas in the balloon a) is halved b) is doubled c) goes down by an indeterminate amount d) stays the same
a) is halved
Non-bonding electrons in a molecule are often called a) lone pairs b) covalent pairs c) octet pairs d) valence electrons e) less-active electrons
a) lone pairs
The ionization energy of an element reflects how much energy is required to remove an electron from an atom. Metal elements typically form cations when they react, and thus have ___________ ionization energies than/as non-metal elements, which form anions. a) lower b) higher c) about the same
a) lower
Which has the largest value (i.e., absolute value—biggest number ignoring the sign) of electron energy in the Bohr model? a) n=1 b) n=2 c) n=3 d) n=10
a) n=1
Which of the following exists as resonance structures? a) nitrate ion b) dioxygen c) aluminum
a) nitrate ion
If I react 8 g of oxygen with 2 g of hydrogen, what is the limiting reactant? 2H₂ + O₂ → 2H₂O a) oxygen b) hydrogen c) Water d) Neither reactant is limiting
a) oxygen
Oxygen atoms are ... a) paramagnetic b) diamagnetic c) pseudomagnetic
a) paramagnetic
Which of the following has an "expanded octet"? a) phosphorus pentachloride b) carbon dioxide c) pandemonium blearyide
a) phosphorus pentachloride
Which type(s) of orbitals can the electron adopt in the n=1 orbit (shell). a) s only b) s and d only c) p only d) s and p only e) p and d only
a) s only
Choose the element which has the lowest ionization energy. a) sodium b) sulfur c) chlorine d) argon e) neon
a) sodium
Another name for sulfur tetrafluoride is a) sulfur(IV) fluoride b) sulfur(VI) fluoride c) sulfur hexafluoride d) sulfur(IV) tetrafluoride
a) sulfur(IV) fluoride
Bond energy (enthalpy) is a) the energy required to break the bond b) the energy required to make the bond c) the energy required to turn the bond inside out
a) the energy required to break the bond
When water vapor condenses... a) the entropy of the system goes down and the entropy of the surroundings goes up even more b) the entropy of the system goes up and the entropy of the surroundings goes down
a) the entropy of the system goes down and the entropy of the surroundings goes up even more
A balloon contains 0.5 mol of helium and a much larger amount of nitrogen. The partial pressure of He is 0.5 atm and the volume of the balloon is 8 L. What is the approximate temperature of the gases in the balloon? a) 100 ºC b) 100 K c) 100 ºF d) 273 K
b) 100 K
The pH of a solution of acetic acid is 4. What is the [OH-]? a) 10 M b) 10⁻¹⁰ M c) 10⁻⁴ M d) 10⁴ M
b) 10⁻¹⁰ M
How many moles of oxygen gas are required to react completely with 24 g of graphite (carbon)? (Hint: elemental carbon has the formula "C".) a) 1 b) 2 c) 2.5 d) 3 e) 3.5
b) 2
How many valence electrons does an alkaline earth metal have? a) 1 b) 2 c) buckle my shoe d) 3 e) 4
b) 2
Hydrogen chloride is a strong acid. If 73 g of hydrogen chloride (MW=36.5 g/mol) is dissolved in water to produce 1000.0 mL of solution, what is the concentration of hydronium ions? a) 1.0 M b) 2.0 M c) 3.0 M d) 4.0 M e) impossible to tell
b) 2.0 M
The pH of a solution of acetic acid is 4.37. What is the [OH-]? a) 4.37 x 10⁻¹⁰ M b) 2.34 x 10⁻¹⁰ M c) 10⁻⁴°³⁷ M d) 10⁴°³⁷ M
b) 2.34 x 10⁻¹⁰ M
In which case does the entropy of the system decrease? a) water boils b) 2NO₂ (g) → N₂O₄ (g) c) N₂O₄ (g) → 2NO₂ (g)
b) 2NO₂ (g) → N₂O₄ (g)
The subshells in the n=3 shell of a multi-electron atom increase in energy (become less negative) in the order: a) 3p 3s 3d b) 3s 3p 3d c) 3s 3d 3p 3f d) 3s 3p 3d 3f e) they all have the same energy
b) 3s 3p 3d
What is the pH of a 0.1 mM solution of hydrochloric acid? a) 1 b) 4 c) -1 d) -4
b) 4
If 21% of the molecules in this room are dioxygen and the total pressure is 26 in. Hg, what is the partial pressure of dioxygen? a) 2 in. Hg b) 5 in. Hg c) 0.5 in. Hg d) 1 in. Hg
b) 5 in. Hg
Water is electrolyzed according to the reaction 2H₂O = 2H₂ + O₂ If 11.2 L of hydrogen gas are produced at STP, how many L of oxygen gas are produced? a) 11.2 L b) 5.6 L c) 22.4 L
b) 5.6 L
What is the pH of a solution which is 0.001 M sulfuric? a) 1 b) <3 c) between 3 and 7 d) between 7 and 10
b) <3
The name of the compound that forms between bromine and calcium is a) Calcium brominide b) Calcium bromide c) Bromine calcium d) Bromide calcium e) Bromium calcide
b) Calcium bromide
What is the formula of copper(II) oxide? a) Cu₂O b) CuO c) CuO₂ d) Cu₂O₂
b) CuO
How do we know the energy of the n=1 level of the H atom? a) It can be calculated from the speed of light and Planck's constant b) It is the energy necessary to remove the e⁻ from the H atom c) It was told to Bohr when he was abducted by aliens
b) It is the energy necessary to remove the e⁻ from the H atom
Induced dipole/induced dipole forces are also called a) dipole-dipole interactions b) London dispersion forces c) hydrogen bonding d) ion-dipole interactions
b) London dispersion forces
To obey the octet rule, an oxygen atom will a) Lose 1 electron b) Lose 2 electrons c) Lose 6 electrons d) Gain 1 electron e) Gain 2 electrons steal one of the 9 lives from a cation
b) Lose 2 electrons
What is the formula of magnesium sulfate? a) Mg₂SO₄ b) MgSO₄ c) Mg₂(SO₄)₂ d) Mg(SO₄)₂
b) MgSO₄
For the unbalanced reaction CO + O₂ → CO₂ if I start with 28 g of CO (MW=28 g/mol) and have a theoretical yield of 36 g of CO₂ (MW=44 g/mol), the limiting reactant must be a) CO b) O₂ c) CO₂
b) O₂
A student has 5.4 L of an ideal gas and finds by its mass that it must contain 1.2 moles. The temperature on the day of the measurement is 25°C, and the pressure of the gas is 760 torr, What can we say about the student's work? a) These measurements are correct. b) There must be a mistake in one or more of these measurements. c) There is not enough information to determine whether or not the work is correct.
b) There must be a mistake in one or more of these measurements.
The quantum mechanical model describes the electron around the nucleus as: a) a particle which moves around the nucleus in a wave-like orbit b) a standing wave c) a particle whose circumference matches the size of its orbit d) a particle of varying negative charge according to orbit number
b) a standing wave
Pick the polar molecule (polar compound): a) methane b) acetic acid c) acetate ion d) benzene e) carbon dioxide
b) acetic acid
Which has the lowest boiling point? a) water b) ammonia c) zirconium (Zr)
b) ammonia
The single covalent bond in HBr is formed by the overlap of a) a p orbital on H and a p orbital on Br b) an s orbital on H and a p orbital on Br c) a p orbital on H and an s orbital on Br
b) an s orbital on H and a p orbital on Br
According to the Bohr model of the atom, the energies of the electrons around an atom a) have positive values b) are quantized c) equal n, the orbit number d) are quantificated e) get further apart as n increases
b) are quantized
The ozone molecule is a) bent and non-polar b) bent and polar c) linear and polar d) linear and non-polar
b) bent and polar
The sulfur dioxide molecule is a) bent and non-polar b) bent and polar c) linear and polar d) linear and non-polar
b) bent and polar
What is the pH of a solution made by dissolving 0.30 g of acetic acid in water to make 500 mL of solution? a) between 0 and 2 b) between 2 and 7 c) between 7 and 12 d) > 12
b) between 2 and 7
To which of the following is it not appropriate to assign a "molecular weight"? a) nitrogen dioxide b) calcium bromide c) carbon tetrachloride d) water e) sulfur trioxide
b) calcium bromide
Choose the ionic compound with the largest lattice energy a) sodium chloride b) calcium oxide c) potassium bromide d) nitrogen dioxide
b) calcium oxide
Which molecule contains the most polar bond? a) methane b) carbon dioxide c) dihydrogen
b) carbon dioxide
Pick the strongest acid a) acetic b) chloric c) hypobromous d) hydrofluoric
b) chloric
Which ion is isoelectronic with nitrogen? a) carbon monoxide b) cyanide c) dioxygen d) perchlorate
b) cyanide
Any bond in a molecule is polar if the two atoms held together by the bond a) differ in their core electrons. b) differ in electronegativity. c) are of the same element.
b) differ in electronegativity.
To double the concentration of oxygen gas dissolved in water (T constant), one would have to a) double the vapor pressure of oxygen gas b) double the partial pressure of oxygen gas above the water c) double the volume of the gas above the water d) double the total pressure of all gases above the water by increasing the pressure of nitrogen e) double the temperature in K
b) double the partial pressure of oxygen gas above the water
Which of the following is NOT a feature of Bohr's atomic model: a) electrons circle the nucleus in orbits of quantized energy b) electron orbit energies are directly proportional to orbit number c) light is released when electrons jump down from orbit to orbit d) electron orbit radii are quantized
b) electron orbit energies are directly proportional to orbit number
If I decrease the heat capacity of the liquid on a warming curve, what happens to the slope of the curve? a) gets smaller b) gets larger c) stays the same
b) gets larger
On a Boltzmann plot (molecular speed on x-axis, # of molecules with each speed on y-axis) as the T rises, the curve a) gets taller and wider b) gets shorter and wider c) gets taller and narrower d) gets shorter and narrower
b) gets shorter and wider
The specific heat capacity of iron is 0.5 J/g•K. If I heat equal masses of water and iron at the same rate, which will get hotter faster? a) water b) iron c) they both get hotter at the same rate
b) iron
The lattice energy of CaS is _______ that of NaCl (in terms of the magnitude of the number, ignoring the sign). Assume only charge matters. a) smaller than b) larger than c) the same size as
b) larger than
Metals are found on the ____ side of the periodic table and typically react by _____. a) left ...gaining electrons b) left ... losing electrons c) right ... gaining electrons d) right ... losing electrons e) wrong ... mugging electrons
b) left ... losing electrons
Choose the electron transition which will absorb the photon of smallest ν. a) n=1 to n=3 b) n=4 to n=5 c) n=6 to n=5 d) n=4 to n=2 e) n=4 to n=3
b) n=4 to n=5
Are all molecules that contain polar bonds polar? a) yes b) no
b) no
In a hydrogen/nitrogen balloon, are the hydrogen molecules moving at the same speed as the nitrogen molecules? a) yes b) no
b) no
What type of orbital is represented by 8? a) s b) p c) d d) f
b) p
Which name represents a real compound which must include an atom with an expanded octet in order to form? a) sulfur dioxide b) phosphorus pentabromide c) neon octafluoride d) cesium nitrate
b) phosphorus pentabromide
The sum of the oxidation numbers of the atoms in the nitrate ion equals: a) 0 b) 1 c) -1 d) 2 e) -2
c) -1
The C-C bond order in benzene is.. a) 1 b) 1.33 c) 1.5 d) 2
c) 1.5
A balloon contains both nitrogen and oxygen gases. If the total gas pressure in the balloon is 2.0 atm and the partial pressure of oxygen is 0.4 atm, what is the partial pressure of nitrogen? a) 1 atm b) 0.4 atm c) 1.6 atm
c) 1.6 atm
If I mix 16 g of oxygen gas with 14 g of nitrogen gas and 4 g of helium gas in a container, what is the mole fraction of nitrogen? a) 1/2 b) 1/5 c) 1/4
c) 1/4
What is the C to O bond order in carbon dioxide? a) 1 b) 1.5 c) 2 d) 3
c) 2
Example: When the following unbalanced reaction is performed, 3 mol aluminum is mixed with 3 mol chlorine. The theoretical yield of aluminum chloride is Al(s) + Cl₂(g) → AlCl₃(s) a) 1 mol b) 1.5 mol c) 2 mol d) 2.5 mol e) 3 mol
c) 2 mol
A π bond is formed by the overlap of the following 2 orbitals on adjacent atoms: a) an s orbital and a p orbital b) 2 unhybridized s orbitals c) 2 unhybridized p orbitals d) 2 hybridized s orbitals
c) 2 unhybridized p orbitals
The number of lone pairs in 2 mol of dinitrogen is: a) 6.0 x 10²³ b) 3.0 x 10²³ c) 2.4 x 10²⁴ d) 0.33 mole
c) 2.4 x 10²⁴
What is the volume of 1 mol of an ideal gas at 1 atm pressure and 0.00 ºC? (R = 0.082 L-atm/K-mol) a) 100.0 L b) 1.00 L c) 22.4 L
c) 22.4 L
sp2 hybrid orbitals always come in sets of a) 1 b) 2 c) 3 d) 4 e) 5
c) 3
How many sigma and pi bonds, respectively, are found in acetylene? a) 1,2 b) 2,2 c) 3,2 d) 4,1 e) 5,0
c) 3,2
Which subshell "fills" with electrons on the periodic table after the 4s subshell? a) 4p b) 3p c) 3d d) 4d e) 4f
c) 3d
How many moles of nitrogen atoms are found in 45 L of nitrogen gas at STP? a) 1 b) 2 c) 4 d) 8
c) 4
The number of electrons in covalent bonds in 2 mol of calcium nitrate dihydrate is a) 8 mol b) 24 mol c) 48 mol d) 6.0 x 10²⁵ e) there are no covalent bonds in this compound—it is ionic
c) 48 mol
How many g of iron metal will be formed if 51 g of aluminum oxide (FW = 102 g/mol) are produced? Fe₂O₃ + 2Al = 2Fe + Al₂O₃ a) 1 g b) 28 g c) 56 g d) 84 g e) 112 g
c) 56 g
If I dissolve 2 moles of calcium chloride in water, how many ions are found in the resulting solution? a) 2 mol b) 4 mol c) 6 mol d) 8 mol
c) 6 mol
What is the molar mass (molecular weight) of carbon disulfide to 2 significant digits in g/mol? a) 34 b) 56 c) 76 d) 24 e) 48
c) 76
Acetic acid is a weak acid. If 120 g of acetic acid (MW=60 g/mol) is dissolved in water to produce 1000.0 mL of solution, what is the concentration of hydronium ions? a) 1.0 M b) 2.0 M c) <2.0 M d) >2.0 M e) 0
c) <2.0 M
It is experimentally determined that the ratio of C atoms to H atoms in a compound is 1:2. If the molecular weight is found to be 42 g/mol, what is the molecular formula? a) C₂H₄ b) C₂H₁₈ c) C₃H₆ d) C₄H₋₆
c) C₃H₆
Which of the following is the electron configuration of potassium? a)₁₉K⁺ b) ₁₅P³⁻ c) [Ar]4s¹ d) 1s² 2s² 2p⁶ 3s² 3p³ e) [Ne] 3s² 3p³
c) [Ar]4s¹
The ammonium ion is a) an anion held together by ionic bonds b) a cation held together by ionic bonds c) a cation held together by covalent bonds d) a canion held together by US Savings Bonds
c) a cation held together by covalent bonds
A double bond consists of a) 2 π bonds b) 2 σ bonds c) a π bond and a σ bond d) a σ bond and a λ bond
c) a π bond and a σ bond
Delocalized pi bonding is found in a) methane b) cyanide ion c) benzene d) more than 1 of the above
c) benzene
Which solvent is least likely to dissolve table salt? a) water b) methanol (the alcohol of methane) c) benzene d) ethanol e) ammonia
c) benzene
What is the pH of a solution which is 0.001 M acetic acid? a) 1 b) <3 c) between 3 and 7 d) between 7 and 10
c) between 3 and 7
ΔH for a reaction can be estimated by adding together the energies (really enthalpies) required to a) break all the bonds in the reactants and break all the bonds in the products b) form all the bonds in the reactants and break all the bonds in the products c) form all the bonds in the products and break all the bonds in the reactants
c) form all the bonds in the products and break all the bonds in the reactants
The ammonia molecule a) is non-polar b) has an "electron domain geometry" (some texts) which is square planar c) has polar bonds and is polar
c) has polar bonds and is polar
Pick what is often the strongest intermolecular force when comparing interactions between molecules of similar size: a) dipole-dipole interactions b) London dispersion forces c) hydrogen bonding d) dipole-induced dipole
c) hydrogen bonding
Which kind of light has the longest wavelength? a) visible b) ultraviolet c) infrared
c) infrared
AgNO₃ (aq) + NaCl (aq) → AgCl (s) + NaNO₃ (aq) If I wrote the equation as a "net ionic equation", what species would not appear in the equation? a) silver ion b) silver chloride c) nitrate ion d) chloride ion
c) nitrate ion
Which is a covalent compound that does NOT obey the octet rule? a) methane b) ozone c) nitrogen dioxide d) calcium bicarbonate e) Donald Trump's toupée
c) nitrogen dioxide
Choose the binary polar compound which is a free radical. a) cyanide ion b) carbon disulfide c) nitrogen monoxide
c) nitrogen monoxide
When an ionic compound dissolves in water, the process a) is always endothermic b) is always exothermic c) results in an increase in entropy for the system d) always involves an increase in enthalpy for the system e) defies all the known laws of nature
c) results in an increase in entropy for the system
Compare the equilibrium vapor pressure of water in "ideal" containers. In which container will the vapor pressure of water be highest? a) a bottle in which the total gas pressure is 0.1 atm b) a bottle in which the total gas pressure is 10 atm c) same vapor pressure in both
c) same vapor pressure in both
I have a solution. When I add a tiny sample of solid solute to the solution, a large amount of precipitate forms. The solution must have been: a) unsaturated b) saturated c) supersaturated
c) supersaturated
Which describes CF2Cl2? a) trigonal planar, sp3 hybridization, non-polar b) tetrahedral, sp3 hybridization, non-polar c) tetrahedral, sp3 hybridization, slightly polar
c) tetrahedral, sp3 hybridization, slightly polar
In aromatic compounds... a) the electrons in the ring are localized b) the sigma bond electrons in the ring are delocalized c) the pi bond electrons in the ring are delocalized d) two of the above
c) the pi bond electrons in the ring are delocalized
The limiting reactant in a reaction is: a) always the first reactant listed b) always the last reactant listed c) the reactant which runs out first d) the reactant which runs out last e) two of the above
c) the reactant which runs out first
When the number of sets of electrons (some texts "electron domains") around the central atom is 5, the arrangement in space of electron sets is a) triangular b) tetrahedral c) trigonal bipyramidal d) octahedral e) dodecahedral
c) trigonal bipyramidal
A neutralization reaction always produces a) an acid b) a base c) water d) a strong electrolyte
c) water
For the reaction 2H₂O (l) = H₃O⁺ (aq) + OH⁻ (aq) a) ΔE > ΔH b) ΔE < ΔH c) ΔE ≈ ΔH d) there is no ΔE
c) ΔE ≈ ΔH
What is the density of water? a. 1.00 lb/mL b. 50.0 g/m³ c. 1.00 g/cm³ d. 5.00 g/L
c. 1.00 g/cm³
An O atom or ion always differs from an F atom or ion in: a. The number of neutrons in the nucleus b. The number of electrons c. The number of protons in the nucleus
c. The number of protons in the nucleus
Absolute 0 on the Kelvin scale is equivalent to a) 0 ºC b) 200 ºC c) 300 ºC d) -273 ºC e) 273 ºC
d) -273 ºC
The temperature outside fell by 50 ºF overnight, which is a change of __________ ºC. a) -10 b) -17 c) -5 d) -28
d) -28
A solution is made by dissolving 1.0 g of methanol in 1.0 L of water. The molar concentration of methanol is approximately a) 0.0005 b) 1.0 c) ½ d) 0.03 e) 1.0 x 10³
d) 0.03
Which solution is more acidic (has higher concentration of hydronium ions)? a) 0.1 M acetic acid HAc (weak) b) 0.1 M hydrochloric acid HCl (strong) c) 0.1 M carbonic acid H₂CO₃(weak, weak) d) 0.1 M sulfuric acid H₂SO₄ (strong, weak)
d) 0.1 M sulfuric acid H₂SO₄ (strong, weak)
How many grams of methanol (the alcohol of methane) would one add to water to make 2.0 L of a 2.0 M solution of methanol (MW= 32 g/mol)? a) 32 g b) 64 g c) 96 g d) 128 g
d) 128 g
What is the pH of a strontium hydroxide solution in which [Sr²⁺] = 5.0 x 10⁻² M? a) 1 b) 3 c) 14 d) 13 e) 12.7
d) 13
Which kind of MO always has a planar node? a) π b) π* c) σ d) 2 of the above
d) 2 of the above
The number of electrons in a double covalent bond is a) 1 b) 2 c) 3 d) 4 e) 5
d) 4
The number of bonding and lone pairs, respectively, in the nitrate ion is a) 1,3 b) 2,1 c) 3,6 d) 4,8 e) 3,1
d) 4,8
The oxidation state of chlorine in the chlorate ion is: a) -3 b) 2 c) 3 d) 5 e) 0
d) 5
How many g of dioxygen are required for the complete combustion of 15 g of ethane (C₂H₆)? a) 16 b) 32 c) 48 d) 56 e) 80
d) 56
The maximum number of electrons which can adopt 2p waveforms (occupy 2p orbitals) is a) 1 b) 2 c) 3 d) 6 e) a bushel and a peck
d) 6
What is the pH of a 1.0 M solution of ethanol (the alcohol of ethane)? a) 0 b) 1 c) 10⁻¹ d) 7
d) 7
2Al(s) + 3Cl₂(g) → 2AlCl₃(s) We calculated the theoretical yield to be 2 mol. If the actual yield was 1.6 mol, the % yield is: a) 1.6 b) 16 c) 160 d) 80
d) 80
Two e⁻'s can adopt the same orbital waveform ("occupy the same orbital") because a) They have opposite charges b) They have different masses c) They have the same social security number d) They have opposite spins
d) They have opposite spins
What were the problems with the Bohr model? a) Only worked quantitatively for H b) Didn't explain why the energies of the orbits are quantized c) It didn't explain the structure of the atom d) a and b e) all the above
d) a and b
Hydrocarbons that contain C-C double bonds are called ______; those that contain C-C triple bonds are called ______. a) alkanes, alkones b) alkenes, alkanes c) alkynes, alkenes d) alkenes, alkynes
d) alkenes, alkynes
When potassium bromide dissolves in water... a) the K+ and Br- ions separate b) each ion is "solvated" by being surrounded by water molecules c) the water molecules around the K+ ion are oriented with the O side pointing inward d) all of a-c
d) all of a-c
"0.1 M H₃O+ " translated into English says a) the solution contains 0.1 mole H₃O+ per liter b) the solution is 0.1 molar H₃O+ c) the molarity of H₃O+ in the solution is 0.1 d) all of the above
d) all of the above
In which case(s) does the entropy of the system go up? a) ice melts b) a gas is heated c) 2C₂H₆(g) + 7O₂(g) = 4CO₂(g) + 6H₂O(g) d) all of the above
d) all of the above
Which of the following classes of compounds effects the pH when dissolved in water? a) alkene b) alcohol c) cylcoalkane d) amine
d) amine
Which of the following form(s) a zwitterion in solution? a) carboxylic acid b) amine c) alcohol d) amino acid e) more than 1 of these
d) amino acid
The conjugate base of sulfuric acid is a) sulfate ion b) water c) amphoteric sulfate d) bisulfate ion
d) bisulfate ion
Which species contains the weakest covalent bond (smallest bond energy)? a) nitrate ion b) dioxygen c) magnesium bromide d) dihydrogen (aka hydrogen)
d) dihydrogen (aka hydrogen)
The rate of effusion or diffusion of a gas is a) directly proportional to the molecular weight (MW) b) proportional to the MW squared c) proportional to the square root of the MW d) inversely proportional to the square root of the MW e) the same no matter what the MW
d) inversely proportional to the square root of the MW
The vapor pressure of a liquid is reached when a) the partial pressure of the vapor is 1 atm b) the vapor pressure is 1 atm c) the liquid has reached its boiling point d) molecules are vaporizing at the same rate as they are condensing
d) molecules are vaporizing at the same rate as they are condensing
Choose the electron transition which will produce the photon of smallest λ. a) n=1 to n=3 b) n=4 to n=5 c) n=6 to n=5 d) n=4 to n=2 e) n=4 to n=3
d) n=4 to n=2
In a mercury barometer, the mercury is a) pulled up the tube by the vacuum at the top b) pulled up the tube by the second law of thermodynamics c) pushed up the tube by the evaporation of the mercury at the base d) pushed up the tube by the pressure of the air
d) pushed up the tube by the pressure of the air
On a warming curve, the length of the line representing fusion is proportional to a) the heat capacity of the liquid b) the heat capacity of the solid c) the heat capacity of the liquid and solid combined d) the heat of fusion of the solid
d) the heat of fusion of the solid
How many moles of sodium (Na) atoms are found in 46 g of sodium?
2.0
The density of water is 1.00 g/cm³. What is the density in lb/m³? (1 lb=454 g)
2.20 x 10³ lb/m³
What is the mass in g of 1 million billion tantalum (Ta) atoms? (Atomic Weight = 181 g/mol)
3 x 10⁻⁷ g
How many protons and neutrons are in the following atom? ¹³C
6 & 7
If I have 3.6 x 10²⁸ atoms, how many moles (of atoms) do I have?
60,000 mol 6.0 x 10⁴ mol
In the Bohr model of the atom, as n gets larger, the energy of the electron approaches
0
How many moles of H atoms are in 2.0 g of C2H6 ? (e.g., in a typical balloon)
0.4 mol
The energy of Bohr orbits in a H atom varies as
1/n²
If I have 6.0 x 10²⁴ peanuts, how many moles (of peanuts) do I have?
10 mol
A ring contains ~33 g of gold (Au)? How many gold atoms are in the ring?
10²³
I have a balloon containing 1/6 mol He. How many He atoms are in the balloon?
10²³
A moment in history: Saddam Hussein decides that the air in his air-tight cell in Baghdad is too dry (% humidity=0), so he sets out a bowl of water to humidify the air while he is out for his daily interrogation. After some time, a) the total gas pressure in the room increases b) the partial pressure of nitrogen in the room decreases c) the mole fraction of dioxygen in the room remains unchanged d) the number of moles of gas molecules in the room decreases
a) the total gas pressure in the room increases
Above the critical temperature and pressure a) there is no separate liquid or gas phase b) the substance exists as a super-duper-critical fluid c) all molecular bonds are broken d) the entropy of the universe decreases
a) there is no separate liquid or gas phase
A sample of ideal gas A has the same volume as a sample of ideal gas B at the same T and P. The molar mass of A is twice that of B. What is true of the 2 samples? a) they contain the same number of molecules b) they have the same density c) sample A contains twice as many molecules as sample B d) sample B contains twice as many molecules as sample A
a) they contain the same number of molecules
How do lone pairs affect the bonds in a molecule or ion? a) they push the bonding pairs closer together b) they pull the bonding pairs further apart c) they have no effect
a) they push the bonding pairs closer together
Families of elements are found in columns (and/or rows) on the periodic table. They are grouped together because they are similar in their a) type and number of valence (outermost) electrons and therefore chemical behavior b) atomic weights c) atomic numbers d) political leanings
a) type and number of valence (outermost)
The solubility of silver(I) bromide is 7.35 x 10⁻⁷ M. A silver(I) bromide solution in which [Br-] = 5.0 x 10⁻⁷ M is a) unsaturated b) saturated c) supersaturated d) hypersaturated e) impossible
a) unsaturated
Do all polar molecules contain polar bonds? a) yes b) no
a) yes
Is nitrogen dioxide a free radical? a) yes b) no
a) yes
The heat of vaporization of water is 540 cal/g. Approximately how much heat passes from the surroundings to the system when 0.1 mol of water evaporates? a) ~1000 cal b) ~540 cal c) ~1800 cal d) ~10 kcal
a) ~1000 cal
A continual bar of color with black lines depicts...
an absorption spectrum
If I mix 16 g of oxygen gas with 7 g of nitrogen gas in a container, what is the mole fraction of nitrogen? a) 0.5 b) 0.33 c) 0.25 d) 0.001
b) 0.33
What is the formal charge on the nitrogen atom in the nitrate ion? a) 0 b) 1 c) 2 d) -1 e) -2
b) 1
How many g of nitric acid (MW= 63 g/mol) should I add to make 2.0 L of a solution with pH=2? a) 5.1 b) 1.3 c) 14. d) 0.13 e) 12.7
b) 1.3
What is the C-O bond order in carbonate ion? a) 1 b) 1.3 c) 2 d) 3
b) 1.3
How much faster will a gas diffuse at 700 ºC than at 0 ºC? a) 700 x b) 1.9 x c) 3.6 x
b) 1.9 x
Heat is represented as a) q, and is released from system to surroundings when endothermic b) q, and is released from system to surroundings when exothermic c) E, and is released from system to surroundings when endothermic d) T, with a negative value when molecules are moving faster than the speed of light
b) q, and is released from system to surroundings when exothermic
The hybridization around the carbon atom in the carboxylic acid "functional group" is a) sp b) sp² c) sp³ d) sp²d e) sp³d
b) sp²
We can rightly designate the central C atom in propane (the 3-C alkane) as a) sp² b) sp³ c) sp⁴
b) sp³
The sp3 hybrid orbitals point towards the corners of a(n) a) triangle b) tetrahedron c) trigonal bipyramid d) octahedron
b) tetrahedron
When removing electrons from any atom, the electrons that come off first are... a) the last in the list in the electron configuration b) the electrons with the highest principle quantum number c) the turquoise electrons
b) the electrons with the highest principle quantum number
Demo from last time: The can crushes because a) the energy of the universe decreases in the process b) the gas pressure inside the can suddenly becomes much less than that outside the can c) cold cans shrink
b) the gas pressure inside the can suddenly becomes much less than that outside the can
If I mix 1 mol of oxygen at 300 K with 1 mol of nitrogen at 300 K in a 22.4-L inelastic bottle, a) the total gas P is ~1 atm b) the total gas P is ~2 atm c) the total gas P is ~1.5 atm d) the T of the mixture is 600 K e) the T of the mixture is 0 K
b) the total gas P is ~2 atm
At sea level, the boiling point of a liquid is reached when a) the partial pressure of the vapor is less than its vapor pressure b) the vapor pressure is 1 atm c) the liquid has reached its equilibrium vapor pressure d) molecules are vaporizing at the same rate as they are condensing
b) the vapor pressure is 1 atm
In a diatomic molecule, a molecular orbital with electron density which is radially symmetrical about the bond axis, has e density in the bond axis, and pulls the molecule together is a) σ* b) σ c) π d) π*
b) σ
Pb & C: Why do the two samples have such different weights when they are about the same size? a. the lighter sample contains fewer atoms that have bigger diameters b. the heavier sample contains more atoms c. each atom in the lighter sample contains He d. the atomic weight of C is smaller than that of Pb
d. the atomic weight of C is smaller than that of Pb
The oxidation state of nitrogen in the dinitrogen molecule is: a) 1 b) 2 c) 3 d) -2 e) 0
e) 0
A solution is made by dissolving 1.0 g of methanol (the alcohol of methane) in 1.0 L of water. The concentration of the methanol in ppm is approximately a) 0.10 b) 1.0 c) 10. d) 1.0 x 10² e) 1.0 x 10³
e) 1.0 x 10³
Let's see if you got it: The carbonate ion has a C-O bond order of ____ and the ion is/is not polar. a) 1, is b) 2, is not c) 1.5, is d) 2.5, is not e) 1.3, is not
e) 1.3, is not
In which type(s) of compound do we find at least one carbon atom surrounded by trigonal planar geometry. (i.e., the atoms bonded to the carbon atom are arranged with this geometry)? a) amine b) aromatic c) alkane d) alkene e) 2 of these
e) 2 of these
Which of the following does/do NOT affect the pH when dissolved in water? a) carboxylic acid b) cycloalkane c) amine d) alcohol e) 2 of these
e) 2 of these
When the following combustion reaction is balanced with whole numbers, the stoichiometric coefficient of oxygen gas is___. CH₃OH + ___O₂ → CO₂ + H₂O a) 0 b) 1 c) 1.7 d) 2 e) 3
e) 3
What is the molar mass (molecular weight) of ozone to 2 significant digits in g/mol? a) 3 b) 8 c) 16 d) 24 e) 48
e) 48
The formula of aluminum perchlorate is a) Al₂Cl₄ b) Al₂ClO₄ c) AlClO₃ d) Al(ClO₄)₂ e) Al(ClO₄)₃
e) Al(ClO₄)₃
Calcium reacts with nitrogen to form a) Ca₂N₂ b) Ca₂N₃ c) Ca₃N₃ d) CaN₃ e) Ca₃N₂ f) CaNada
e) Ca₃N₂
What is the Lewis symbol of Ca⁺? a) Ca b) Ca⁺ c) Ca· d) Ca: e) [·Ca]⁺
e) [·Ca]⁺
Which element(s) exist(s) in nature as diatomic molecules? a) H b) O c) N d) halogens e) all of the above
e) all of the above
In which case does the entropy of the universe increase? a) water boils b) CO₂ dissolves in water c) N₂O₄ (g) → 2NO₂ (g) d) a Chem 105 student gets an A e) all of these
e) all of these
Which process fits under example type 4 (Entropy of system DOWN, of surroundings DOWN)? a) water is raised to its critical temperature and pressure b) a baby is born c) the Roman Empire collapses d) a Big Mac is consumed e) none of these
e) none of these
Which of the following is not a unit of pressure? a) psi b) pascal c) atmosphere d) torr e) ton
e) ton
Which of the following is the correct symbol of a negative cation? a. Na2- b. Na2- c. 2Na d. Na2+ e. None of these
e. None of These
The wavelength of light varies ________ as its frequency.
inversely
Light as a particle: A particle of light is called a....
photon
We say the energy of a light photon is...
quantized
The speed of light is equal to
λν
