Question

Consider the following statements: "Heat is a form of energy, and energy is conserved. The heat lost by a system must be equal to the amount of heat gained by the surroundings. Therefore, heat is conserved." Indicate everything you think is correct in these statements. Indicate everything you think is incorrect. Correct the incorrect statements and explain.

Short answer

The statements "Heat is a form of energy" and "Energy is conserved" are correct. However, the conclusion "Therefore, heat is conserved" is incorrect. The correct conclusion should be "Therefore, energy is conserved." While heat can be transferred and converted between systems, the total energy in the system and its surroundings remains constant. This highlights the importance of understanding the distinction between heat as a specific form of energy and the broader concept of energy conservation.

Step-by-step solution

Identify the correct statements

The first statement, "Heat is a form of energy," is correct. Heat is indeed a form of energy, specifically thermal energy, which is transferred between objects or systems due to a difference in temperature. The second statement, "Energy is conserved," is also correct. This is in reference to the law of conservation of energy, which states that energy cannot be created or destroyed, only transferred or converted from one form to another.

Identify incorrect statements and correct them

The third statement, "The heat lost by a system must be equal to the amount of heat gained by the surroundings. Therefore, heat is conserved," is partially incorrect. The first part of this statement is true – when heat is transferred between a system and its surroundings, the heat lost by the system is equal to the heat gained by the surroundings. However, the conclusion "Therefore, heat is conserved" is incorrect. The correct statement should be "Therefore, energy is conserved." This is because while heat itself is not conserved (as it can be converted to and from other forms of energy), the total energy within the system and its surroundings remains constant during the heat transfer process.

Explain the corrections

The correction made in Step 2 highlights the difference between heat and energy conservation. Heat is a form of energy, but it is not conserved on its own, as it can be transferred between systems and converted to or from other forms of energy. The key concept here is the conservation of total energy – which includes all forms of energy, not just heat. By making this correction, we emphasize the importance of understanding the distinction between heat as a specific form of energy and the broader concept of energy conservation.