Question

Which of the following statements are correct as per IUPAC sign convention?
A.The work done by the system on the surrounding is negative
B.The work done by the surrounding on the system is positive
C.The heat absorbed by the system from the surrounding is positive
D.The heat absorbed by the surrounding from the system is positive

Answer 1

Hint:This is a question from the topic thermodynamics. In this topic there are many sign conventions given by IUPAC which we need to follow. Based on this we will answer the following question. The work done to the system is positive and the work done by the system is negative.

Complete answer:
Thermodynamics is a branch of physics that deals with heat, work, temperature, and their relation to energy, radiation and physical properties of matter. The first law specifies that energy can be exchanged between physical systems as heat and work. The second law defines the existence of a quantity called entropy, that describes the direction, thermodynamically, that a system can evolve and quantifies the state of order of a system and that can be used to quantify the useful work that can be extracted from the system.
The first option is that the work done by the system on the surrounding is negative. From the convention given by IUPAC, this statement is correct.
The second option is that the work done by the surrounding on the system is positive. From the convention given by IUPAC. This statement is correct. Now we will check the next option.
The third option is that the heat absorbed by the system from the surrounding is positive. From the convention given by IUPAC this is also correct.
The fourth option is that the heat absorbed by the surrounding from the system is positive. As the previous option is correct so this option is incorrect.
So this question has multiple correct answers.

So, the correct options are A, B, C.

Note:
IUPAC stands for International Union of Pure and Applied Chemistry. When there are three answers correct as in the above question then two conditions arise, either we have to answer all the correct options or we will answer the remaining incorrect one. So the question should be read properly.