An ideal gas undergoes a process from state 1 (T1 = 300

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An ideal gas undergoes a process from state 1 (T₁ = 300 K, p₁ = 100 kPa) to state 2 (T₂ = 600 K, p₂ = 500 kPa). The specific heats of the ideal gas are: c_p = 1 kJ/kg-K and c_v = 0.7 kJ/kg-K. The change in specific entropy of the ideal gas from state 1 to state 2 (in kJ/kg-K) is _________ (correct to two decimal places)

1. 0.3 kJ/kg-K
2. 0.2 kJ/kg-K
3. 0.4 kJ/kg-K
4. - 0.3 kJ/kg-K

Correct Option: A

Ideal gas
State - 1: T₁ = 300 K, P₁ = 100 kPa
State - 2: T₂ = 600 K, P₂ = 500 kPa,
c_p = 1 kJ/kg-K, c_p – c_v = R, c_v = 0.7 kJ/kg-K
⇒ c_p – c_v = 1 – 0.7 = R
R = 0.3 kJ/kg– K
Change in specific entropy

= 1 ×ln		600	- R ln	P₂
		300		P₁