Question

Determine whether the statements given below are true or false. Consider an endothermic process taking place in a beaker at room temperature. (a) Heat flows from the surroundings to the system. (b) The beaker is cold to the touch. (c) The pressure of the system decreases. (d) The value of \(q\) for the system is positive.

Short answer

Question: Based on the analysis of an endothermic process taking place in a beaker at room temperature, determine whether the following statements are true or false: a) Heat flows from the surroundings to the system. b) The beaker is cold to the touch. c) The pressure of the system decreases. d) The value of \(q\) for the system is positive.

Step-by-step solution

Statement (a) - Heat flows from the surroundings to the system

Since the process is endothermic, it means that the system is absorbing heat from its surroundings. Therefore, heat flows from the surroundings to the system. This statement is true.

Statement (b) - The beaker is cold to the touch

As heat is being absorbed from the surroundings by the system, it will lead to a decrease in the temperature of the surroundings, of which the beaker is a part. Thus, the beaker will be colder than the system and hence, cold to the touch. Therefore, this statement is true as well.

Statement (c)- The pressure of the system decreases

The pressure of a system depends on the nature of the reaction, temperature, and volume. We cannot determine just from the given information whether the pressure of the system decreases or not during the endothermic process. So, this statement is neither true nor false due to insufficient information.

Statement (d) - The value of \(q\) for the system is positive

An endothermic process is characterized by the absorption of heat by the system, which implies that the heat (\(q\)) involved is positive. Therefore, the value of \(q\) for the system is positive, and this statement is true.

Key concepts

Thermodynamics

Thermodynamics is the branch of physical science that deals with the relations between heat and other forms of energy. In particular, it describes how thermal energy is converted to and from other forms of energy and how it affects matter.

An endothermic process, which is the focus of our exercise, is a fundamental concept in thermodynamics. During such a process, energy is absorbed from the surroundings into the system. This transfer of energy typically occurs in the form of heat. The system, which could be a chemical reaction or physical change, takes in heat, resulting in an overall decrease in the temperature of the surroundings.

For instance, when a chemical reaction in a beaker absorbs heat from the room (the surroundings), the system (the reaction mixture) gains energy. This will lead to a decrease in the room temperature, which can cause the beaker to feel cold to the touch. This transfer of energy is not only important for understanding reactions in a laboratory setting but is also widely applicable in natural processes and engineering applications.

Heat Transfer

Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and phase changes.

In the context of our endothermic process, heat transfer occurs from the surroundings to the system. When heat is absorbed by the system, the energy must come from somewhere, which is usually the immediate surroundings. In our example, the surroundings would be the air and the beaker that are in direct contact with the system.

As the system absorbs heat, the temperature of the system increases, while the temperature of the surroundings decreases. This is a direct application of the conservation of energy, which is a fundamental principle in thermodynamics. The idea that the beaker becomes cold to the touch is a tangible example of this heat transfer, which occurs until thermal equilibrium is reached or the endothermic process is complete.

System and Surroundings

In thermodynamics, 'system' refers to the part of the universe that is under consideration, often separated from the rest of the universe by a boundary. The 'surroundings' are everything outside that boundary. In simpler terms, the system is what you're focusing on or studying, while the surroundings are the environment around the system.

It's vital to make this distinction because the behavior of a thermodynamic system is often studied in relation to its surroundings. Whether a process is endothermic or exothermic is determined by the direction of heat transfer between the system and the surroundings.

For an endothermic process, such as the one described in the exercise, the system is absorbing heat, which must come from the surroundings. Therefore, there is a clear distinction between the system, which gains energy, and the surroundings, which lose energy. Understanding this interaction is crucial for accurately describing and predicting the behavior of thermodynamic systems in real-life scenarios.