Question 1

+ O₂(g) --> 2SO₃(g)
What is the correct rate law for this reaction?

Accepted Answer

When writing a rate law for a chemical reaction, use the concentrations of the reactants raised to the powers of their coefficients. The rate constant, k, is determined experimentally and cannot be determined with the information in this problem. Thus, the correct rate law is r = k[SO₂]2[O₂].

Question 2

Which of the following molecules exhibits resonance?

Accepted Answer

Resonance occurs when two or more bonds show double bond character. This effect occurs when a double bond in either location is energetically equal. The best way to identify resonance is to draw Lewis structures. In the context of this question, O₃ is the only molecule to exhibit resonance.

Question 3

Cobalt has an atomic mass of 59 and an atomic number of 27. What does this information reveal about most cobalt atoms?

Accepted Answer

Cobalt atoms, with an atomic mass of 59 and an atomic number of 27, have more neutrons (59 - 27 = 32) than protons (27).

Question 4

Three identical balloons each contain one mole of gas. One balloon contains oxygen, one contains nitrogen, and one contains argon. Which of the following changes in volume will happen if the balloons are placed in a warmer room?

Accepted Answer

According to the ideal gas law (PV=nRT), the volume of a gas is directly proportional to its temperature when pressure and the amount of gas (n) are held constant. Since each balloon contains one mole of gas and they are all subjected to the same temperature increase, they will all increase in volume equally, regardless of the type of gas.

Question 5

A student adds iron filings to a copper(II) chloride solution at room temperature. A balanced equation for the reaction that occurs is shown below. Fe_(s) + CuCL₂(aq) → FeCL₂(aq) + Cu_(s) Which of the following changes would most likely increase the reaction rate?

Accepted Answer

Increasing the concentration of the CuCl2 solution increases the number of Cu2+ ions in the solution, which can interact with the iron filings, thus increasing the reaction rate.

Question 6

The equation below shows the reaction of ammonia with water: NH₃(q) + H₂O(I) ↔ NH₄+(aq) + OH^-_(aq) According to the Brønsted-Lowry theory of acids and bases, which of the following is acting as the acid for the forward reaction?

Accepted Answer

In the forward reaction, H₂O donates a proton (H⁺) to NH₃, acting as the Brønsted-Lowry acid.

Question 7

Iron(II) chloride (FeCL₂) is a product of the reaction between iron metal (Fe) and hydrochloric acid (HCl), as shown in the equation below. Fe + 2HCl → FeCL₂ + H₂. What is the change in oxidation number of iron in this reaction?

Accepted Answer

In the reaction, iron starts with an oxidation number of 0 (as it is in its elemental form) and ends with an oxidation number of +2 in iron(II) chloride (FeCl2), indicating it has lost two electrons.

Question 8

The reduction of carbon dioxide by hydrogen gas takes place at 420°C to produce water vapor and carbon monoxide. The equation for this reaction at equilibrium is shown below. H_2(g) + CO_2(g) ↔ H₂O_(g)+ CO_(g). Which of the following changes in concentration occur when more water vapor is added to the system under equilibrium conditions?

Accepted Answer

The answer of The reduction of carbon dioxide by hydrogen...

Question 9

A neutral atom has an outer shell electron configuration of 2s22p6. To which of the following groups of elements does it belong?

Accepted Answer

The electron configuration 2s2 2p6 indicates a full outer shell, which is characteristic of noble gases. This configuration specifically corresponds to neon (Ne), a noble gas.

Question 10

Which of the following statements best explains why water has a high surface tension?

Accepted Answer

Water has a high surface tension because of the strong hydrogen bonds between the neighboring polar water molecules. These intermolecular forces pull the molecules closer together, creating a "tight" surface.

Question 11

The average distance between molecules always increases during which of the following phase changes?

Accepted Answer

During the phase change from liquid to gas, molecules overcome intermolecular forces to move apart, thus increasing the average distance between them.

Question 12

Which of the following ideas was proposed by Niels Bohr?

Accepted Answer

Niels Bohr proposed the idea that electrons occupy specific, quantized energy levels within an atom. This concept is a fundamental aspect of the Bohr model of the atom, which was a significant advancement in atomic theory, moving away from the earlier models that did not account for quantized energy states.

Question 13

Carbon reacts with chlorine to form CCl4. What is the name of this compound?

Accepted Answer

Carbon tetrachloride is the correct name for CCl4, indicating one carbon atom and four chlorine atoms.

Question 14

A walk -in cooler has a volume of 1.1 X 104 L. If the temperature inside the cooler is 3°C and the gas pressure is 1.0 atm, how many moles of gas are inside the cooler?

Accepted Answer

Using the ideal gas law, $PV = nRT$, where $P = 1.0 \, \text{atm}$, $V = 1.1 \times 10^4 \, \text{L}$, $R = 0.0821 \, \text{L atm mol}^{-1} \text{K}^{-1}$, and $T = 3°C = 276 \, \text{K}$, we can solve for $n$, the number of moles of gas. Rearranging the equation gives $n = \frac{PV}{RT}$. Substituting the given values, $n = \frac{(1.0 \, \text{atm})(1.1 \times 10^4 \, \text{L})}{(0.0821 \, \text{L atm mol}^{-1} \text{K}^{-1})(276 \, \text{K})}$, which calculates to approximately $4.9 \times 10^2 \, \text{mol}$.

Question 15

Which of the following statements best explains why ionic solids dissolve in water?

Accepted Answer

Water's high polarity allows it to surround and stabilize ions, leading to the dissolution of ionic solids.

Question 16

The chemical equation below represents sulfur trioxide (SO₃) in the atmosphere mixing with rainwater to form sulfuric acid (H₂SO₄), which is a major component of acid rain: SO₃(g) + H₂O(I) → H₂SO_4(I) The molar mass of SO₃ is 80.1 g/mol and the molar mass of H₂SO₄ is 98.1 g/mol. How much H₂SO₄ is produced when 128.0 g of SO₃ mixes with rainwater?

Accepted Answer

128.0 g of SO₃ is 1.6 moles (128.0 g / 80.1 g/mol). Since the reaction is a 1:1 molar ratio, 1.6 moles of H₂SO₄ are produced. 1.6 moles of H₂SO₄ is 157 g (1.6 moles * 98.1 g/mol).

Question 17

Which of the following statements explains why the human body produces chemical buffers?

Accepted Answer

Buffers are crucial for maintaining a constant pH in the blood, which is essential for the proper functioning of enzymes and other biochemical processes in the body.

Question 18

0 M solution of HCl is diluted to 1.0 M. How many milliliters of the 6.0 M solution would be used to prepare 100.0 mL of the diluted 1.0 M solution?

Accepted Answer

The answer of 0 M solution of HCl is diluted...

Question 19

After crude oil is pumped out of the ground, it must be processed in a "cracking tower." The tower separates it into less dense chemicals like butane and gasoline, and more dense chemicals like diesel fuel and tar. Based on this information, crude oil can best be classified as a

Accepted Answer

Crude oil is a mixture of different hydrocarbon compounds, which are separated into various products through the process of fractional distillation in a cracking tower.

Question 20

When a cup of hot chocolate cools from 90°C to 80°C, which of the following is happening to the molecules of the liquid?

Accepted Answer

The rate of motion of molecules decreases as the temperature decreases, which is what happens when the hot chocolate cools from 90°C to 80°C. This is because temperature is a measure of the average kinetic energy of the molecules, so a decrease in temperature means a decrease in their kinetic energy and thus their rate of motion.

Quiz 1: CLEP: Chemistry and Biology

+ O₂(g) --> 2SO₃(g) What is the correct rate law for this reaction?

Which of the following molecules exhibits resonance?

Cobalt has an atomic mass of 59 and an atomic number of 27. What does this information reveal about most cobalt atoms?

Three identical balloons each contain one mole of gas. One balloon contains oxygen, one contains nitrogen, and one contains argon. Which of the following changes in volume will happen if the balloons are placed in a warmer room?

A student adds iron filings to a copper(II) chloride solution at room temperature. A balanced equation for the reaction that occurs is shown below. Fe_(s) + CuCL₂(aq) → FeCL₂(aq) + Cu_(s) Which of the following changes would most likely increase the reaction rate?

The equation below shows the reaction of ammonia with water: NH₃(q) + H₂O(I) ↔ NH₄+(aq) + OH^-_(aq) According to the Brønsted-Lowry theory of acids and bases, which of the following is acting as the acid for the forward reaction?

Iron(II) chloride (FeCL₂) is a product of the reaction between iron metal (Fe) and hydrochloric acid (HCl) , as shown in the equation below. Fe + 2HCl → FeCL₂ + H₂. What is the change in oxidation number of iron in this reaction?

A neutral atom has an outer shell electron configuration of 2s22p6. To which of the following groups of elements does it belong?

Which of the following statements best explains why water has a high surface tension?

The average distance between molecules always increases during which of the following phase changes?

Which of the following ideas was proposed by Niels Bohr?

Carbon reacts with chlorine to form CCl4. What is the name of this compound?

A walk -in cooler has a volume of 1.1 X 104 L. If the temperature inside the cooler is 3°C and the gas pressure is 1.0 atm, how many moles of gas are inside the cooler?

Which of the following statements best explains why ionic solids dissolve in water?

Which of the following statements explains why the human body produces chemical buffers?

0 M solution of HCl is diluted to 1.0 M. How many milliliters of the 6.0 M solution would be used to prepare 100.0 mL of the diluted 1.0 M solution?

After crude oil is pumped out of the ground, it must be processed in a "cracking tower." The tower separates it into less dense chemicals like butane and gasoline, and more dense chemicals like diesel fuel and tar. Based on this information, crude oil can best be classified as a

When a cup of hot chocolate cools from 90°C to 80°C, which of the following is happening to the molecules of the liquid?

Quiz 1: CLEP: Chemistry and Biology

+ O₂(g) --> 2SO₃(g) What is the correct rate law for this reaction?

Which of the following molecules exhibits resonance?

Cobalt has an atomic mass of 59 and an atomic number of 27. What does this information reveal about most cobalt atoms?

Three identical balloons each contain one mole of gas. One balloon contains oxygen, one contains nitrogen, and one contains argon. Which of the following changes in volume will happen if the balloons are placed in a warmer room?

A student adds iron filings to a copper(II) chloride solution at room temperature. A balanced equation for the reaction that occurs is shown below. Fe(s) + CuCL2(aq) → FeCL2(aq) + Cu(s) Which of the following changes would most likely increase the reaction rate?

The equation below shows the reaction of ammonia with water: NH3(q) + H2O(I) ↔ NH4+(aq) + OH-(aq) According to the Brønsted-Lowry theory of acids and bases, which of the following is acting as the acid for the forward reaction?

Iron(II) chloride (FeCL2) is a product of the reaction between iron metal (Fe) and hydrochloric acid (HCl) , as shown in the equation below. Fe + 2HCl → FeCL2 + H2. What is the change in oxidation number of iron in this reaction?

A neutral atom has an outer shell electron configuration of 2s22p6. To which of the following groups of elements does it belong?

Which of the following statements best explains why water has a high surface tension?

The average distance between molecules always increases during which of the following phase changes?

Which of the following ideas was proposed by Niels Bohr?

Carbon reacts with chlorine to form CCl4. What is the name of this compound?

A walk -in cooler has a volume of 1.1 X 104 L. If the temperature inside the cooler is 3°C and the gas pressure is 1.0 atm, how many moles of gas are inside the cooler?

Which of the following statements best explains why ionic solids dissolve in water?

Which of the following statements explains why the human body produces chemical buffers?

0 M solution of HCl is diluted to 1.0 M. How many milliliters of the 6.0 M solution would be used to prepare 100.0 mL of the diluted 1.0 M solution?

After crude oil is pumped out of the ground, it must be processed in a "cracking tower." The tower separates it into less dense chemicals like butane and gasoline, and more dense chemicals like diesel fuel and tar. Based on this information, crude oil can best be classified as a

When a cup of hot chocolate cools from 90°C to 80°C, which of the following is happening to the molecules of the liquid?

A student adds iron filings to a copper(II) chloride solution at room temperature. A balanced equation for the reaction that occurs is shown below. Fe_(s) + CuCL₂(aq) → FeCL₂(aq) + Cu_(s) Which of the following changes would most likely increase the reaction rate?

The equation below shows the reaction of ammonia with water: NH₃(q) + H₂O(I) ↔ NH₄+(aq) + OH^-_(aq) According to the Brønsted-Lowry theory of acids and bases, which of the following is acting as the acid for the forward reaction?

Iron(II) chloride (FeCL₂) is a product of the reaction between iron metal (Fe) and hydrochloric acid (HCl) , as shown in the equation below. Fe + 2HCl → FeCL₂ + H₂. What is the change in oxidation number of iron in this reaction?