An ideal gas mixture consists of 4 kg of Ar and 6 kg of CO₂ gases. The mixture is now heated at constant volume from 275 K to 325 K. The amount of heat transfer is A)485 kJ B)716 kJ C)519 kJ D)834 kJ E)1687 kJ

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T1=225 "K"
T2=325 "K"
Cv1=0.3122; Cp1=0.5203 "kJ/kg.K"
Cv2=0.657; Cp2=0.846 "kJ/kg.K"
m1=4 "kg"
m2=6 "kg"
MM1=39.95 "kg/kmol"
MM2=44 "kg/kmol"
"Applying Energy balance gives Q=DeltaU=DeltaU_Ar+DeltaU_CO2"
Q=(m1*Cv1+m2*Cv2)*(T2-T1)
"Some Wrong Solutions with Common Mistakes:"
W1_Q = (m1+m2)*(Cv1+Cv2)/2*(T2-T1) "Using arithmetic average of properties" 
W2_Q = (m1*Cp1+m2*Cp2)*(T2-T1)"Using Cp instead of Cv"
W3_Q = (m1*Cv1+m2*Cv2)*T2 "Using T2 instead of T2-T1"

An Ideal Gas Mixture Consists of 4 Kg of Ar