Question

A gaseous system absorbs 600 kg of heat and perform the work of expansion equal to 130 kg. The internal energy change is ...1)730 kg 2)470 kg 3)730 kg 4) 470 kg

Answer 1

Answer:

option d) 470 kj

Explanation:

600 + (-130)

470

Answer 2

Given:

Heat absorbed into the gaseous system= Q= 600 KJ

Work done by the system = W= -130 KJ (∵ work is of expansion)

To find:

Internal energy change in the system= ΔU

Step-wise solution:

• The change in the internal energy of the system is given by first law of thermodynamics.

• According to this law, total heat transferred into the system minus total work done by the system is defined as change in internal energy of the system.

It is numerically expressed as:

ΔU = Q + W

where ΔU= change in internal energy of the system

ΔU = 600 KJ + (-130KJ)

ΔU = 600 KJ - 130 KJ

ΔU = 470 KJ

Hence, the internal energy change in gaseous system is 470 KJ.