A tank of volume 0.05 m3 contains a mixture of saturated

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A tank of volume 0.05 m³ contains a mixture of saturated water and saturated steam at 200°C. The mass of the liquid present is 8 kg. The entropy (in kJ/kgK) of the mixture is ________ (correct of two decimal places) Property data for saturated steam and water are: At 200ºC [P_sat = 1.5538 MPa] v_f = 0.001157 m³/kg, v_g = 0.12736 m³/kg s_fg = 4.1014 kJ/kgK, s_f = 2.3309 kJ/kgK

1. s = 2.4884 kJ/kg-K
2. s = 1.4884 kJ/kg-K
3. s = 3.4884 kJ/kg-K
4. s = 4.4884 kJ/kg-K

Correct Option: A

Total volume of tank (V) = 0.05 m³
Means of liquid (m²) = 8 kg

V_V = m_V V_V
V_V = V_g @ 200°C
= 0.12736 m³ /kg
V_V = m_V L_L
V_L = V_f @ 200°C
= 0.001157 m³ /kg
V_L = 8 × 0.001157
= 9.256 × 10^-3 m³
0.05 = 9.256 × 10^-3 + V_V
V_V = 0.0474 m³
0.04074 = m_V × 0.12736
m_V = 0.3198 kg

x =	0.3198
	0.3198 + 8

⇒x = 0.0384
Specific entropy of mixture(s)
s = s_f + xs_fg
s = 2.3309 + 0.0384 × 4.1014
s = 2.4884 kJ/kg-K