physical science unit 3 test chapter 18

Order energy from most ordered to least ordered

1. Gravitational Potential Energy and Kinetic Energy 2. Nuclear Potential Energy 3. Electric Potential Energy 4. Chemical Potential 5. Thermal Energy

A car can't convert all of the energy from its fuel to macroscopic kinetic energy. Why?

Entropy would decrease.

Figure 1 shows that gas molecules are present inside the box. Figure 2 shows that there is a vacuum (no gas molecules present) inside of the box. If the two figures represent snapshots in time of an irreversible process, which figure came first and why?

Figure 2: Because an empty box is more ordered.

Complete conversion of one form of energy to another can occur only in the direction

from higher to lower organized forms

e. An ice cube floating in a glass of water at zero degrees is what kind of process

ideal reversible process

In an irreversible process, the overall disorder of the universe

increases

_____ the temperature of a gas increases the disorder.

increasing

An ice cube melts in a glass of warm water. This is an example of which type of process?

irreversible

A reversible process does what to the total disorder in the universe?

It does not change.

We see a large amount of order in the world around us from life to currents in the air and ocean. How is this consistent with the Law of Increasing Disorder?

It is because the sun provides additional high-order energy to the world to create this order.

Which of the following correctly applies the law of increasing disorder to an air conditioner?

It is true that the heat flow from the cold region to the hotter region increases order, but this is made up for by increasing the disorder of energy from another source.

A perfume bottle drops and shatters on the floor of a room. (An irreversible process has just occurred - the breaking of the bottle!) You observe that you can smell the perfume throughout the entire room a few seconds later. Explain this observation in terms of the Molecular Model of Matter (Chapter 13) and the Law of Increasing Disorder.

The perfumes odor is caused by its molecules. Molecules of perfume in the liquid are in random motion. When the bottle breaks, the molecules can vaporize and spread throughout the room, mixing with the air in the room. The room with perfume molecules spread around it is more disordered than with them concentrated in a spot surrounding the broken bottle.

A window air conditioner is normally placed in a window so the hot air from the back blows outside. What would happen if the air conditioner were placed in the middle of a closed room and turned on?

The room would heat up because all of the energy absorbed by the air conditioner, both thermal and electrical potential, is released back into the room as thermal energy.

Which of the following forms of energy is the least ordered?

Thermal

Which type of energy is the most ordered?

b. Gravitational potential energy

In the future, engineers will be able to design a car that is turns 100% of the energy in the gasoline into kinetic energy.

false

The 2nd Law of Thermodynamics (Law of Increasing Disorder) places limits on the efficiency of energy conversion. Which of the following is allowed?

d. 100% conversion of electricity to ambient temperature thermal energy. ( if higher goes to lower energy)

The gasoline engine of an automobile is considerably less than 100% efficient. This means that not all of the energy in the gasoline is turned into kinetic energy of the car. Which of the following best explains why?

d. Some of the chemical potential energy in the gasoline must become ambient thermal energy if the rest is to supply the kinetic energy of the automobile. This means some energy must be wasted. Correct

Entropy measures the _____ of a system.

disorder