At STP, the mass of 10.0 L of an unknown monatomic gas is 17.8 g. The atomic mass of the gas is equal to a) 7.94 u b) 224 u c) 39.9 u d) 3.71 u e) 0.447 u A Carnot engine receives 5.0 kJ of heat from the high-temperature reservoir and rejects 3.0 kJ of heat into the low-temperature reservoir. The efficiency of the engine is equal to a) 0.62 b) 0.66 c) 0.40 d) 0.25 e) 0.60 Two charges, -6.0 nC and +2.0 nC, are separated by a distance of 3.0 m, as shown in the diagram below. The electric field at the midpoint (P) between the charges is equal to a) 32 N/C directed to the left b) 16 N/C directed to the left c) 8.0 N/C directed to the right d) 16 N/C directed to the right e) 32 N/C directed to the right -60nc + 2-On C 1.5m 1.5m