General Chemistry 4-6

What is the pH of a 0.001 M solution of sulfuric acid? (pK_a = -2.8), assuming complete dissociation?

A. 0

B. 1

C. 2

D. 3

E. 4

3

Which of the following is the correct molecular geometry of PCl₅?

A. Bent

B. Trigonal planar

C. Tetrahedral

D. Trigonal bipyramidal

E. Octahedral

Trigonal bipyramidal

Which of the following elements undergoes oxidation in the unbalanced equation for the chemical reaction below?

NaCl + H₂SO₄ + MnO₂ → Na₂SO₄ + MnSO₄ + H₂O + Cl₂

A. Oxygen

B. Manganese

C. Sulfur

D. Chlorine

E. Sodium

Chlorine

Which of the following bonds is the most polar?

A. C-H

B. O-F

C. C-C

D. C-N

E. O-H

O-H

Radioactive decay is the spontaneous breakdown of an atomic nucleus resulting in the release of energy and matter from the nucleus. What order kinetics does radioactive decay follow?

A. Zero-order kinetics

B. First-order kinetics

C. Second-order kinetics

D. Third-order kinetics

First-order kinetics

The distance separating two adjacent carbon nuclei is 1.54 Å and the bond length in F₂ is 1.32 Å. Based on this data, which of the following is the length of the C-F bond in CF₄?

A. 1.21

B. 1.36

C. 1.43

D. 1.54

E. 1.62

1.43

According to the following reaction, how many grams of Fe₂O₃ are formed when 15 g of iron is combusted?

4 Fe  +   3 O₂  →  2 Fe₂O₃

A. 

B. 

C. 

D. 

E. 

d

What is the heat of formation for one mole of ethane gas (C₂H₆) if ΔH_f^o for ethene gas (C₂H₄) is +50.5 kJ•mol^-1?

C₂H_4(g) + H_2(g) → C₂H_6(g)         ΔH= -125.1 kJ

A. 26.4 kJ

B. -24.1 kJ

C. -74.6 kJ

D. -119.7 kJ

E. -175.6 kJ

-74.6 kJ

It takes 180 g of benzene at a density of 0.832 g•mL^-1 to fill a container. At constant temperature, what mass of petroleum ether (0.64 g•mL^-1) is needed to fill the same container?

A. 

B. 

C. 

D. 

E. 

d

For the reaction below, which of the following sets of coefficients would balance the reaction?

C₇H₁₀N + O₂ → CO₂  + H₂O  + __NO₂

A. 2, 24, 14, 10, 2

B. 2, 21, 14, 10, 2

C. 2, 18, 10, 10, 2

D. 2, 24, 10, 8, 2

E. 2, 21, 8, 12, 2

2, 21, 14, 10, 2

Elements that have 7 electrons in their outermost shell and commonly form salts during chemical reactions are collectively known as

A. metals.

B. non-metals.

C. inert gases.

D. noble gases.

E. halogens.

halogens.

Which of the following elements has the lowest electron affinity?

A. Li

B. B

C. O

D. F

E. Ne

Ne

Given 15 moles of nitrogen gas are present in an 8 L container at 25^oC, what is the pressure of the nitrogen gas? (R = 8.314 L•kPa•K^-1•mol^-1)

A. 

B. 

C. 

D. 

E. 

A

Which of the following is true for a reaction that has a small negative ΔG value?

A. Products will be favored at equilibrium

B. Reactants will be favored at equilibrium

C. No reactants will remain at equilibrium

D. No products will remain at equilibrium

E. No reaction would occur

Products will be favored at equilibrium

Which of the following best represent the decay process shown below?

238	U	→	234	Th
92			90

A. Alpha decay

B. β^- decay

C. β⁺ decay

D. Electron capture

E. Gamma decay

Alpha decay

Which of the following would cause a random error?

A. pH meter calibrated incorrectly

B. Reading the meniscus at a different angle each time

C. Spilling the product

D. Electronic balance tarred incorrectly

E. Thermometer reading 103°C in pure boiling water

Reading the meniscus at a different angle each time

A 35 g metal alloy at 25^oC absorbs 2.5 kJ of energy, raising its temperature to 35^oC. What is the specific heat of the alloy, in J•g•^-1•^oC^-1?

A. 

B. 

C. 

D. 

E. 

a

At which point during a titration experiment does pH = pK_a ?

A. Half-equivalence point

B. Equivalence point

C. Triple point

D. Second equivalence point

E. Critical point

Half-equivalence point

What is the ionic reaction for the neutralization of HCl with NaOH?

A. HCl_(aq) + NaOH_(aq) ↔ H₂O_(l) + NaCl_(aq)

B. H⁺_(aq) + Cl^-_(aq) + Na⁺_(aq) + OH^-_(aq) ↔ H⁺_(aq) + OH^-_(aq) + Na⁺_(aq) + Cl^-_(aq)

C. H⁺_(aq) + Cl^-_(aq) + Na⁺_(aq) + OH^-_(aq) ↔ H₂O_(l) + Na⁺_(aq) + Cl^-_(aq)

D. H⁺_(aq) + Cl^-_(aq) + Na⁺_(aq) + OH^-_(aq) ↔ H₂O_(l) + NaCl_(s)

E. H⁺_(aq) + Cl^-_(aq) + Na⁺_(aq) + OH^-_(aq) ↔ H⁺_(aq) + O_2(g) + Na⁺_(aq) + Cl^-_(aq)

c

What process occurs when the vapor pressure of a liquid equals the atmospheric pressure?

A. Melting

B. Freezing

C. Boiling

D. Sublimation

E. Condensation

Boiling

Each of the following pairs of compounds forms hydrogen bonds with each other EXCEPT one. Which one is the EXCEPTION?

A. CH₃CH₂OH and H₂O

B. NH₂CH₃ and CO

C. NH and HF

D. H₂O and H₂O₂

E. H₂S and HCl

H₂S and HCl

If the temperature of a gas is halved at constant pressure, the volume

A. will be halved.

B. will be reduced to a third.

C. will triple.

D. will double.

E. will not change.

will be halved.

At 37°C, which one of the following solutions produces the lowest osmotic pressure?

A. 0.90 M fructose

B. 0.40 M MgSO₄

C. 0.40 M (NH₄)₂SO₄

D. 0.32 M Na₂SO₄

E. 1.0 M sucrose

0.40 M MgSO₄

Based on the data shown below, what is the initial activity of the radioactive sample at the start (zero hours) if the half-life is 12 hours?

A. 3,437

B. 3,525

C. 3,650

D. 3,700

E. 3,835

3700

Which of the following gas laws states that two gases with equal volumes will have an equal number of molecules at the same temperature and pressure?

A. Boyle’s Law

B. Dalton’s Law

C. Gay-Lussac’s Law

D. Charles’ Law

E. Avogadro’s Law

Avogadro’s Law

The reaction of oxalate ions (C₂O₄^2-) with permanganate ions (MnO₄^-) in acidic solution forms carbon dioxide (CO₂) and manganese(II) ions (Mn²⁺). What is the stoichiometric coefficient in front of oxalate ion in the balanced redox equation?

A. 2

B. 3

C. 5

D. 7

E. 10

5

The atomic theory states that matter is composed of

A. particles.

B. elements.

C. molecules.

D. atoms.

E. compounds.

atoms

How many equivalent resonance structures can be drawn for the nitrate ion, NO₃^-?

A. 1

B. 2

C. 3

D. 4

E. 5

3

Each of the following reactions has an equilibrium point that is affected by changes in pressure EXCEPT one. Which one is the EXCEPTION?

A. Li₂S_(aq) + HBr_(aq) → 2 LiBr_(aq) + H₂S_(g)

B. 2 H_2(g) + O_2(g) → 2 H₂O_(g)

C. 2 Na_(s) + Cl_2(g) → 2 NaCl_(s)

D. C_(s) + H₂O_(g) → CO_(g) + H_2(g)

E. CS_2(l) + 3 O_2(g) → CO_2(g) +2 SO_2(g)

CS_2(l) + 3 O_2(g) → CO_2(g) +2 SO_2(g)

In which of the following compounds does sulfur have an oxidation number of +2?

A. S₂O₃^2-

B. SO₂

C. S₂O₆^2-

D. SO₄^2-

E. H₂S

S₂O₃^2-

Which of the following is true regarding pi bonds and sigma bonds?

A. Pi bonds are stronger than sigma bonds

B. Sigma bonds are formed by overlapping lateral orbitals 

C. Pi bonds allow for rotation

D. A triple bond contains one sigma and two pi bonds

E. Pi bonds are formed by end-to-end overlapping orbitals

A triple bond contains one sigma and two pi bonds

Aqueous NH₃ was titrated with HBr until the endpoint. The resulting solution underwent testing using four pH indicators, and the table below provides information about the indicators and the colors observed during the test. Based on the information provided, which of the following statements is correct? 

A. pH at endpoint is 4.8

B. pH at endpoint is 6.1

C. pH at endpoint is 12.0

D. pH at endpoint is 2.4

E. pH at endpoint is 7.0

pH at endpoint is 4.8

Which of the following best describe bond energy?

A. Energy required for a reaction to proceed

B. Energy required to break a bond

C. Energy required to create a bond

D. Energy required to maintain a bond

Energy required to break a bond

If it takes 95 g of diesel at a density of 0.832 g•mL^-1 to fill a container, at constant temperature, what mass of benzene (0.740 g•mL^-1) is needed to fill the same container?

A. 

 

B. 

C. 

D. 

E. 

d

How many protons, neutrons, and electrons does the following anion have? 

A. 4 protons, 3 neutrons and 4 electrons

B. 6 protons, 6 neutrons and 7 electrons

C. 6 protons, 3 neutrons and 4 electrons

D. 3 protons, 3 neutrons and 4 electrons

E. 3 protons, 4 neutrons and 4 electrons

3 protons, 3 neutrons and 4 electrons

All of the following are true regarding Galvanic cells EXCEPT one. Which one is the EXCEPTION?

A. Oxidation occurs at the anode

B. Galvanic cells produce chemical energy

C. Electrons flow from the anode to cathode

D. The salt bridge keeps solutions electrically neutral

E. Metal electrodes gain electrons at the cathode

Galvanic cells produce chemical energy

According to the following reaction, how many grams of Fe₂O₃ are formed when 383 g of iron is combusted?

4 Fe  +   3 O₂  →  2 Fe₂O₃

A. 

B. 

C. 

D. 

E. 

e

Given 5 moles of oxygen gas are present in a 5 L container at 25^oC, what is the pressure of the oxygen gas? (R = 8.314 L•kPa•K^-1•mol^-1)

A. 2,300 kPa

B. 2,400 kPa

C. 2,500 kPa

D. 2,600 kPa

E. 2,700 kPa

2,500 kPa

Each of the following are ionic compounds EXCEPT one. Which one is the EXCEPTION?

A. NH₄NO₂

B. KH

C. LiNO₃

D. CH₃NH₂

E. NaOH

CH₃NH₂

Which of the statements is true for a reaction with a negative ΔH?

A. The reaction will be endothermic

B. The reaction will be non-spontaneous

C. The reaction will be spontaneous

D. The reaction will be exothermic

E. The reaction will not occur

The reaction will be exothermic

How many electrons are involved in the following acidic redox reaction?

MnO₄^- + H₂SO₃ + H⁺ → Mn²⁺ + HSO₄^- + H₂O

A. 2

B. 4

C. 6

D. 8

E. 10

10

How much energy is needed to bring 250 mL of water (4.18 J•g^-1•^oC^-1) at 25^oC to a boil?

A. 

B. 

C. 

D. 

E. 

d

Which of the following is the correct electron configuration for the bromide ion, Br^- ?

A. [Ar] 4s²4d⁵

B. [Ar] 4s²4d¹⁰4p⁶

C. [Ar] 4s²3d¹⁰4p⁶

D. [Ar] 4s²3d¹⁰4p⁶5s¹

E. [Ar] 4s²3d¹⁰3p⁶

[Ar] 4s²3d¹⁰4p⁶

What is the empirical formula of a compound composed of 50.05% sulfur and 49.95% oxygen?

A. SO₂

B. SO₃

C. SO₄

D. S₂O₄

E. S₂O₅

SO₂

Given methanol has a density of 0.792 g•cm^-3 at 273 K, what volume of container is needed to hold 0.060 kg of methanol at 273 K?

A. 65 cm³

B. 70 cm³

C. 75 cm³

D. 80 cm³

E. 85 cm³

75 cm³

Which of the following represents the highest value of pressure?

A. 100 kPa

B. 1 atm

C. 780 mmHg

D. 25 torr

E. 96,000 Pa

780 mmHg

Nitrogen gas, hydrogen gas, and ammonia gas were put into a chamber and allowed to react until equilibrium was reached. The reaction is outlined by the following equation:

N_2(g) + 3 H_2(g) → 2 NH_3(g)

If the pressure at equilibrium was more than the initial pressure, what can be said about the reaction quotient and the direction of reaction as the reaction progressed toward equilibrium?

A. Q_c > K_c ; forward reaction

B. Q_c > K_c ; backward reaction

C. Q_c < K_c ; forward reaction

D. Q_c < K_c ; backward reaction

E. Q_c = K_c ; backward reaction

Q_c > K_c ; backward reaction

Which of the following compounds is miscible in water?

A. C₆H₆

B. CH₃COCH₃

C. CH₃CH₂CH₃

D. CCl₄

E. CH₄

CH₃COCH₃

Based on the data shown below, what is the rate law for the following chemical reaction?

A + B → C

Experiment	[A]	[B]	Initial rate (M • s-1)
1	0.1 M	0.1 M	2.0 × 10-5
2	0.2 M	0.1 M	8.0 × 10-5
3	0.1 M	0.2 M	4.0 × 10-5

A. Rate = k[A][B]

B. Rate = k[A][B]²

C. Rate = k[A]²[B]

D. Rate = k[A]²[B]²

E. Rate = k[B]

Rate = k[A]²[B]

Given the titration curve below, what quantity of 0.1 M HCl is required to reach the equivalence point in the titration with 0.1 M of NH₃?

A. 9 mmol

B. 10 mmol

C. 12 mmol

D. 16 mmol

E. 18 mmol

10 mmol

How many moles of oxygen are in a 190 g solution of KNO₃ at a temperature of 28^oC ?

A. 4.8

B. 5.1

C. 5.4

D. 5.7

E. 6.0

5.7

Which of the following compounds contains nitrogen with an oxidation number of -2?

A. N₂H₅⁺

B. NH₃

C. N₂O

D. NO

E. HNO₂

N₂H₅⁺

In a fission reaction, uranium-235 is bombarded with a neutron and decays into two main radioactive fragments and 3 neutrons as depicted in the following reaction:

²³⁵U + ¹n → ¹⁴¹Ba + X + 3¹n

What is the element and the atomic mass of radioactive fragment X?

A. ⁹²U

B. ⁹²Kr

C. ⁹⁵Kr

D. ⁹²Ba

⁹²Kr

Each of the following electron configurations obeys Hund’s Rule EXCEPT one. Which one is the EXCEPTION?

A. 

B. 

C. 

D. 

E. 

E

Using an incorrectly calibrated pipette will result in

A. gross error.

B. random error.

C. systematic error.

D. personal error.

E. method error.

systematic error.

Which of the following represents the solubility product constant for lead chloride?

PbCl_2(s)  ⇌ Pb²⁺_(aq) + 2 Cl^-_(aq)

A. [Pb²⁺][Cl^-]

B. [Pb²⁺][Cl^-]²

C. 2[Pb²⁺][Cl^-]

D. 2[Pb²⁺][Cl^-]²

E. [Pb²⁺]²[Cl^-]

[Pb²⁺][Cl^-]²

Given the enthalpy data for reactions shown below, what is the enthalpy change for the following reaction?

N_2(g) + 2 O_2(g) → 2 NO_2(g)

2 NH_3(g) + 4 H₂O_(l) → 2 NO_2(g) + 7 H_2(g)              ΔH = -140 kJ
2 NH_3(g) → N_2(g) + 3 H_2(g)                                      ΔH = 110 kJ
H₂O_(l) → H_2(g) + ½ O_2(g)                                         ΔH = -50 kJ

A. -100 kJ

B. -50 kJ

C. 50 kJ

D. 100 kJ

E. 250 kJ

-50 kJ

For the reaction below, which of the following sets of coefficients would balance the reaction?

Ca₃(PO₄)₂  + SiO₂ + C → CaSiO₃ + P₄ + CO₂

A. 1, 3, 6, 6, 1, 6

B. 1, 3, 5, 6, 1, 5

C. 1, 3, 5, 3, 1, 5

D. 2, 6, 5, 6, 1, 5

E. 2, 6, 10, 6, 1, 10

2, 6, 5, 6, 1, 5

What does the azimuthal quantum number represent?

A. Orbital size and energy level

B. Quantity of electrons in an orbital 

C. Electron spin direction

D. Shape of the orbital

E. Orbital orientation

Shape of the orbital

A Lewis acid is

A. a proton producer.

B. a proton donor.

C. a proton acceptor.

D. an electron acceptor.

E. an electron donor.

an electron acceptor.

A container with a tightly fitted movable piston contains carbon dioxide gas at 27^oC. What is the change in internal energy of the gas if 200 J of heat enters the gas and the gas does 300 J of work in the process?

A. -500 J

B. -100 J

C. 0 J

D. +100 J

E. +500 J

-100 J

What is the change in boiling point when 5 M of NaCl is dissolved in water? (K_b water = 0.51 ^oC•kg•mol^-1)

A. –(2)(0.51)(5)

B. (0.51)(5)

C. (2)(0.51)(5)

D. –(0.51)(5)

E. (2)(0.51)(10)

(2)(0.51)(5)

Nobelium-259 is a radioactive isotope with a half-life of 60 minutes. If a nobelium-259 sample weighs 3.75 g after 3 hours, how many grams of Nobelium-259 were in the original sample?

A. 1.875 g

B. 7.5 g

C. 15 g

D. 30 g

E. 60 g

30 g

Which of the following represents the equilibrium constant for the weak base, NH₃ in an aqueous solution?

A. 

B. 

C. 

D. 

E. 

c

Given that the rate law for a certain reaction is rate = k[A][B], what is the unit of the rate constant?

A. s^-1

B. M^-1

C. M^-1s^-1

D. M^-1s^-2

E. M^-2s^-1

M^-1s^-1

What is the osmotic pressure of a 1.5 M sucrose solution at 300 K?

A. 3.7 atm  

B. 5.5 atm

C. 37 atm

D. 71 atm 

E. 74 atm

37 atm

Which of the following represents the K_sp of AgCl if the molar solubility is 1.3 × 10^-5?

A. (1.3 × 10^-5)(1.3 × 10^-5)

B. (1.3 × 10^-5)(1.3 × 10^-5)²

C. (1.3 × 10^-5)(2)(1.3 × 10^-5)²

D. (1.3 × 10^-5)²(1.3 × 10^-5)²

E. (1.3 × 10^-5)(2)(1.3 × 10^-5)

(1.3 × 10^-5)(1.3 × 10^-5)

If a gas mixture containing a total of 10 moles has partial pressures of 0.5 atm for O₂, 1.4 atm for N₂, and 0.6 atm for F₂, how many moles of oxygen gas are present in the mixture?

A. 2

B. 2.5 

C. 3.5

D. 5

E. 8

2

Which of the following is true for a reaction with ΔH < 0 J and ΔS < 0 J•K^-1?

A. The reaction is spontaneous at all temperatures

B. The reaction is non-spontaneous at all temperatures

C. The reaction is spontaneous at low temperatures

D. The reaction is spontaneous at high temperatures

The reaction is spontaneous at low temperatures

According to the following reaction, how many grams of hydrogen gas are formed when 54 g of aluminum reacts with 49 g of sulfuric acid?

2 Al + 3 H₂SO₄ → Al₂(SO₄)₃ + 3 H₂

A. 1 g

B. 2 g

C. 3 g

D. 4 g

E. 5 g

1 g

Weaker intermolecular forces result in a higher

A. melting point.

B. vapor pressure.

C. viscosity.

D. surface tension.

E. boiling point. 

vapor pressure.

Acetic acid and its conjugate base acetate (K_a = 1.8 × 10^-5)  can be used to make a simple buffer solution. Which of the following pH indicators would be suitable for monitoring the pH while making this buffer?

A. Methyl yellow (pH 2.9 – 4.0)

B. Congo red (pH 3.0 – 5.0)

C. Bromocresol purple (pH 5.2 – 6.8)

D. Neutral red (pH 6.8 – 8.0)

E. Cresol red (pH 7.2 – 8.8)

Congo red (pH 3.0 – 5.0)

The phase diagram for an unknown compound is given below. If the compound is initially at point A before the pressure is decreased, what is the first phase change that the compound will undergo? 

A. Deposition

B. Fusion

C. Crystallization

D. Vaporization

E. Sublimation

Sublimation

What is the osmotic pressure for 0.20 M of Na₃PO₄ at 30^oC?

A. (0.2)(0.0821)(303)

B. (2)(0.2)(0.0821)(303)

C. (4)(0.2)(0.0821)(30)

D. (4)(0.2)(303)

E. (4)(0.2)(0.0821)(303)

(4)(0.2)(0.0821)(303)

Which of the following is TRUE for reaction coordinates?

A. The difference between the reactant and product energy is the activation energy

B. Energy released in exergonic reactions is the energy difference between products and reactants

C. An intermediate occurs at an energy maximum

D. The difference between the reactant energy and the transition state is the enthalpy

E. The relaxation energy is the negative of the activation energy

Energy released in exergonic reactions is the energy difference between products and reactants

Which of the following is a rate expression for the following reaction?

2 H₂O_(g) → 2 H_2(g) + O_2(g)

A. [H₂O] / 2Δt

B. -Δ [H₂] / 2Δt

C. -Δ [O₂] / 2Δt

D. -Δ [H₂O] / Δt

E. Δ [O₂] / Δt

Δ [O₂] / Δt

Each of the following is a Bronsted-Lowry conjugate acid-base pair EXCEPT one. Which one is the EXCEPTION?

A. HPO₃^2- , PO₃^3-

B. CH₃CH₂CO₂H , CH₃CH₂CO₂^-

C. HNO₃ , HNO₂

D. NH₃ , NH₂^–

E. H₂S , HS^-

HNO₃ , HNO₂

What is the heat of formation for 2 moles of N₂O₅ gas based on the equations below?

        2 N_2(g) + 5 O_2(g) → 2 N₂O_5(g)               ΔH = ?

        H_2(g) + ½ O_2(g) → H₂O_(ℓ)                      ΔH = -250 kJ

        N₂O_5(g) + H₂O_(ℓ) → 2 HNO_3(ℓ)             ΔH = -50 kJ

        N_2(g) + 3 O_2(g) + H_2(g) → 2 HNO_3(ℓ)     ΔH = -350 kJ

A. -100 kJ

B. -150 kJ

C. 50 kJ

D. 650 kJ

E. -50 kJ

-100 kJ

Which of the following is the percent composition of oxygen in glucose, C₆H₁₂O₆?

A. 

B. 

C. 

D. 

E. 

B

A student performs an experimental reaction and recovers 15 g of the product. Based on the amount of reactant used, it was estimated that 20 g of the product should have been obtained. What is the yield of the reaction?

A. (15)/(20)

B. (20-15)/(20)

C. (20-15)/(15)

D. (20)/(15)

E. (15-20)/(20)

(15)/(20)

Each of the following are strong acids EXCEPT one. Which one is the EXCEPTION?

A. HClO₄

B. HBr

C. HF

D. H₂SO₄

E. HClO₃

HF

Which of the following molecules is correctly matched with its bond angle?

A. XeF₂                (120º)
B. SF₆                   (107.4º)
C. SO₄^2-                (<104º)
D. H₂CO               (120º)
E. H₂O                  (109º)

A. XeF₂

B. SF₆

C. SO₄^2-

D. H₂CO

E. H₂O

H₂CO

If 0.92 g of toluene was used to lower the freezing point of 100 g of benzene by 0.50 ^oC (K_f benzene = 5^oC•m^-1), what is the estimated molar mass of toluene used?

A. 75 g•mol^-1

B. 80 g•mol^-1

C. 92 g•mol^-1

D. 90 g•mol^-1

E. 95 g•mol^-1

92 g•mol^-1

If the volume of an ideal gas is doubled and the temperature is tripled, what change does the pressure undergo?

A. 1/6 of the original pressure

B. 2/3 of the original pressure

C. 6 times the original pressure

D. 3/2 of the original pressure

E. 3 times the original pressure

3/2 of the original pressure

Which of the following elements would be strongly attracted to a magnetic field?

A. Ga

B. Zn

C. Ca

D. Mg

E. Ne

Ga

Which of the following molecules has the strongest dipole moment?

A. PF₅

B. CCl₄

C. PBr₃O

D. CO₂

E. CH₄

PBr₃O

Which of the following pairs correctly represents the heat of fusion and heat of vaporization, respectively, for a 36-gram sample of water that requires 102.6 kJ of energy to undergo sublimation?

A. 25.65 kJ•mol^-1; 25.65 kJ•mol^-1

B. 20.2 kJ•mol^-1; 82.4 kJ•mol^-1

C. 42.3 kJ•mol^-1; 9.0 kJ•mol^-1

D. 9.0 kJ•mol^-1; 42.3 kJ•mol^-1

E. 82.4 kJ•mol^-1; 20.2 kJ•mol^-1

9.0 kJ•mol^-1; 42.3 kJ•mol^-1

Which of the following molecules has a linear molecular geometry?

A. PCl₃

B. CH₃Cl

C. XeF₂

D. H₂O

E. O₃

XeF₂

Given a reaction with ΔH = 50 kJ and ΔS = 25 J•K^-1, at what temperature will the reaction become spontaneous?

A. Above 2,000°C

B. Below 2,000 K

C. Above 2,000 K

D. Below 2,000°C

E. Above 2,273 K

Above 2,000 K

Which of the following statements best explains why sodium is more reactive than magnesium?

A. Sodium has a lower atomic radius

B. Sodium has a lower electronegativity

C. Sodium is a metal

D. Group 1 elements are not very reactive

E. Sodium has a higher ionization energy

Sodium has a lower electronegativity