1. A spontaneous chemical reaction
requires higher temperatures to occur
has no activation energy
occurs without any input of energy ***
increases entropy
2. S is
the total kinetic movement in a system
the full range of motions in a system***
the average kinetic movement in a system
the opposite of the Heisenberg Uncertainty Principle
3. A new car will eventually fall apart no matter how well you take care of it. This is best explained by using
the Second Law of Thermodynamics
the Third Law of Thermodynamics
Gay-Lussac's Law
the First Law of Thermodynamics***
4. Which is the best illustration of the Second Law of Thermodynamics?
frost forms on the outside of an ice cube
an ice cube in a freezer slowly shrinks***
an ice cube freezes
an ice cube melts then re-freezes
I agree with 1 (with a caveat), 2 and 4 but not 3. The caveat on 1 is that energy must come from somewhere and that is the system; i.e., the energy is already there in EXCESS so the reaction uses what it needs and the excess is left over. In 1 I think the choices are just not explained very well. In 3 I think the conservation of energy certainly is correct and will be conserved as the car degenerates; however, I don't think that explains why it degenerates in the first place.
1. To determine which statement is true about spontaneous chemical reactions, we need to understand the concept of spontaneity and the factors that influence it. Spontaneous reactions occur without any external influence and proceed naturally. One of the key factors that determine the spontaneity of a reaction is the change in Gibbs free energy (ΔG). For a reaction to be spontaneous, ΔG must be negative.
Now, looking at the four options:
- "Requires higher temperatures to occur" is not true because the spontaneity of a reaction is not dependent on temperature. In fact, some spontaneous reactions may even decrease in rate at higher temperatures.
- "Has no activation energy" is also not true. All reactions, including spontaneous ones, require some amount of activation energy to initiate the reaction.
- "Occurs without any input of energy" is true. Spontaneous reactions occur without any external input of energy. However, it is important to note that spontaneous reactions still involve energy changes within the system.
- "Increases entropy" is also true. Spontaneous reactions tend to increase the overall entropy (disorder) of the system.
Therefore, the correct answer is: A spontaneous chemical reaction occurs without any input of energy.
To arrive at this answer, you could understand the concept of spontaneity and how it relates to ΔG, as well as the relationship between entropy and spontaneity.
2. The term "S" in this context is not specified clearly, and it is difficult to determine the correct answer without additional information. However, I can provide some possibilities based on the answer choices given:
- "The total kinetic movement in a system" is not a widely used or recognized definition for S.
- "The full range of motions in a system" is a more plausible definition for S. In thermodynamics, the term "entropy" (S) is used to describe the measure of disorder or randomness in a system. It represents the range of possible microstates that a system can occupy.
- "The average kinetic movement in a system" is not a direct correlate of entropy.
- "The opposite of the Heisenberg Uncertainty Principle" is not related to the term "S" or entropy.
Therefore, the most reasonable answer based on the given options is: S refers to the full range of motions in a system, which is a characteristic of entropy.
To arrive at this answer, you could consider the different meanings associated with the term "S" and evaluate which definition aligns best with the concept being discussed.
3. The statement that a new car will eventually fall apart, regardless of how well it is taken care of, can be best explained using the concept of the Second Law of Thermodynamics.
The Second Law of Thermodynamics states that, in any isolated system, the entropy (disorder) tends to increase over time. This means that the natural tendency of things is to move towards a state of higher entropy.
In the case of a new car, even if it is well-maintained and taken care of, it is exposed to various factors that can contribute to its deterioration and eventual breakdown. These factors include wear and tear, exposure to the elements, chemical reactions, and heat transfer. As time goes by, these processes increase the entropy of the car's components, leading to their degradation and the eventual breakdown of the car.
Therefore, the best explanation for the statement is: The First Law of Thermodynamics.
To arrive at this answer, you could understand the concept of entropy and the relationship between entropy and the degradation of systems over time.
4. The best illustration of the Second Law of Thermodynamics is an ice cube in a freezer slowly shrinking.
The Second Law of Thermodynamics states that the entropy of an isolated system tends to increase over time. In the case of an ice cube in a freezer, the freezer acts as an isolated system, and the ice cube is exposed to it.
As time passes, the ice cube absorbs heat from the surrounding environment (the freezer) and undergoes a process called sublimation, where it directly changes from a solid state to a gas (water vapor) without passing through the liquid state. This process leads to the slow shrinking or disappearance of the ice cube.
The key point here is that the entropy of the system increases during this process. The solid ice cube (with low entropy) transforms into water vapor (with higher entropy), contributing to the overall increase in entropy.
Therefore, the best illustration of the Second Law of Thermodynamics is an ice cube in a freezer slowly shrinking.
To arrive at this answer, you could understand the concept of entropy, the Second Law of Thermodynamics, and how it relates to the transformation of states in a system.