Rebekah set up a different experiment as shown below. She measured the volume of the liquid and the air in the
cylinders before and after a 200 g load was added to the piston.

When the loads were added to the pistons, the volume of the liquid did not change but the volume of the air decreased.
Explain why this happened

8.29 two streams containing pyridine and acetic acid at 25°c are mixed and fed into a heat exchanger. due to the heat-of-mixing effect, it is desired to reduce the temperature after mixing to 25°c using a stream of chilled ethylene glycol as indicated in the diagram. calculate the mass flow rate of ethylene glycol needed. the heat capacity of ethylene glycol at these conditions is approximately 2.8 kj/(kg k), and the enthalpy change of mixing (δmixh) is given below.