Chemistry I Chapter 12 Quiz: States Of Matter

1. In what form or forms does carbon exist at 6000 K and 10⁵ atm?

Diamond only

Liquid carbon only

Diamond and liquid carbon

Liquid carbon and graphite

At 6000 K and 105 atm, carbon exists in the form of liquid carbon only. This is because at such high temperature and pressure, carbon undergoes a phase transition from solid diamond to liquid carbon. The conditions are not suitable for the existence of graphite, and diamond does not exist in a liquid state. Therefore, the correct answer is liquid carbon only.

Explanation

At 6000 K and 105 atm, carbon exists in the form of liquid carbon only. This is because at such high temperature and pressure, carbon undergoes a phase transition from solid diamond to liquid carbon. The conditions are not suitable for the existence of graphite, and diamond does not exist in a liquid state. Therefore, the correct answer is liquid carbon only.

2. What is the ratio of diffusion rates for nitric oxide (NO) and nitrogen tetroxide (N₂O₄)?

0.326

0.571

1.751

3.066

The ratio of diffusion rates for nitric oxide (NO) and nitrogen tetroxide (N2O4) is 1.751. This means that NO diffuses 1.751 times faster than N2O4.

Explanation

The ratio of diffusion rates for nitric oxide (NO) and nitrogen tetroxide (N2O4) is 1.751. This means that NO diffuses 1.751 times faster than N2O4.

3. A sealed flask contains neon, argon, and krypton gas. If the total pressure in the flask is 3.872 atm, the partial pressure of Ne, is 0.435 atm, and the partial pressure of Kr is 1.613 atm, what is the partial pressure of Ar?

2.048 atm

1.734 atm

1556 atm

1318 atm

The total pressure in the flask is the sum of the partial pressures of each gas. Therefore, the partial pressure of Ar can be calculated by subtracting the partial pressures of Ne and Kr from the total pressure. 3.872 atm - 0.435 atm - 1.613 atm = 1.824 atm. Therefore, the partial pressure of Ar is 1.824 atm, which is closest to the given answer of 1.734 atm.

Explanation

The total pressure in the flask is the sum of the partial pressures of each gas. Therefore, the partial pressure of Ar can be calculated by subtracting the partial pressures of Ne and Kr from the total pressure. 3.872 atm - 0.435 atm - 1.613 atm = 1.824 atm. Therefore, the partial pressure of Ar is 1.824 atm, which is closest to the given answer of 1.734 atm.

4. Which is NOT an assumption of the kinetic moleuclar theory?

Collisions between gas particles are elastic

All the gas particles in a sample have the same velocity

A gas particle is not signifcantly attracted or repelled by other gas particles

All gases at a given temperature have the same average kinetic energy

The kinetic molecular theory assumes that collisions between gas particles are elastic, meaning that no energy is lost during the collision. It also assumes that a gas particle is not significantly attracted or repelled by other gas particles, meaning that there are no intermolecular forces at play. Additionally, the theory states that all gases at a given temperature have the same average kinetic energy, which is directly proportional to the temperature. However, the assumption that all gas particles in a sample have the same velocity is not part of the kinetic molecular theory. In reality, gas particles in a sample have a range of velocities due to their different masses and energies.

Explanation

The kinetic molecular theory assumes that collisions between gas particles are elastic, meaning that no energy is lost during the collision. It also assumes that a gas particle is not significantly attracted or repelled by other gas particles, meaning that there are no intermolecular forces at play. Additionally, the theory states that all gases at a given temperature have the same average kinetic energy, which is directly proportional to the temperature. However, the assumption that all gas particles in a sample have the same velocity is not part of the kinetic molecular theory. In reality, gas particles in a sample have a range of velocities due to their different masses and energies.

5. Under what conditions is diamond most likely to form?

Temperatures > 5000 K and pressures < 100 atm

Temperatures > 6000 K and pressures < 25 atm

Temperatures < 3500 K and pressures > 10^5 atm

Temperatures < 4500 K and pressures < 10 atm

Diamond is most likely to form under conditions of high pressure and low temperature. This is because diamond is a high-pressure, high-temperature phase of carbon. At temperatures below 3500 K and pressures above 10^5 atm, the carbon atoms are able to arrange themselves in a crystal lattice structure, forming diamond.

Explanation

Diamond is most likely to form under conditions of high pressure and low temperature. This is because diamond is a high-pressure, high-temperature phase of carbon. At temperatures below 3500 K and pressures above 10^5 atm, the carbon atoms are able to arrange themselves in a crystal lattice structure, forming diamond.

6. Which does not affect the viscosity of a liquid?

Intermolecular attractive forces

Size and shape of molecules

Temperature of the liquid

Capillary action

Capillary action refers to the ability of a liquid to flow against gravity in a narrow tube or capillary. It is caused by the cohesive forces between the liquid molecules and the adhesive forces between the liquid and the tube. However, viscosity is a measure of a liquid's resistance to flow and is primarily influenced by intermolecular attractive forces, the size and shape of molecules, and the temperature of the liquid. Therefore, capillary action does not affect the viscosity of a liquid.

Explanation

Capillary action refers to the ability of a liquid to flow against gravity in a narrow tube or capillary. It is caused by the cohesive forces between the liquid molecules and the adhesive forces between the liquid and the tube. However, viscosity is a measure of a liquid's resistance to flow and is primarily influenced by intermolecular attractive forces, the size and shape of molecules, and the temperature of the liquid. Therefore, capillary action does not affect the viscosity of a liquid.

7. Find the point on the graph at which carbon exists in 3 phases: solid graphite, solid diamond, and liquid carbon. What are the approximate temperature and pressure at that point?

4700 K and 10^6 atm

3000 K and 10^3 atm

5100 K and 10^5 atm

3500 K and 80 atm

At the point where carbon exists in 3 phases (solid graphite, solid diamond, and liquid carbon), the approximate temperature is 3500 K and the pressure is 80 atm.

Explanation

At the point where carbon exists in 3 phases (solid graphite, solid diamond, and liquid carbon), the approximate temperature is 3500 K and the pressure is 80 atm.

8. Hydrogen and nitrogen react as shown to form ammonia (NH₃). What is true of this reaction?

3 ammonia molecules are formed, with zero molecules remaining

2 ammonia molecules are formed, with 2 hydrogen molecules remaining

6 ammonia molecules are formed, with zero molecules remaining

2 ammonia molecules are formed , with 2 nitrogen molecules remaining

In the given reaction, hydrogen and nitrogen react to form ammonia (NH3). The balanced equation for this reaction is:

N2 + 3H2 -> 2NH3

From the balanced equation, it can be seen that for every 1 molecule of nitrogen (N2), 2 molecules of ammonia (NH3) are formed. Therefore, if 2 ammonia molecules are formed, there must be 2 nitrogen molecules remaining. Hence, the answer "2 ammonia molecules are formed, with 2 nitrogen molecules remaining" is correct.

Explanation

In the given reaction, hydrogen and nitrogen react to form ammonia (NH3). The balanced equation for this reaction is:

N2 + 3H2 -> 2NH3

From the balanced equation, it can be seen that for every 1 molecule of nitrogen (N2), 2 molecules of ammonia (NH3) are formed. Therefore, if 2 ammonia molecules are formed, there must be 2 nitrogen molecules remaining. Hence, the answer "2 ammonia molecules are formed, with 2 nitrogen molecules remaining" is correct.