The constant-volume heat capacity of a gas can be measured by observing the decrease in temperature when it expands adiabatically and reversibly. if a decrease in pressure is also measured, we can use it to infer the value of γ (the ratio of heat capacities, cp/cv) and hence, by combining the two values, deduce the constant pressure heat capacity. a fluorocarbon gas was allowed to expand reversibly and adiabatically to twice its volume; as a result, the temperature fell from 298.15 k to 248.44 k and its pressure fell from 1522.2 torr to 613.85 torr. evaluate cp.

Cp=42.58 J/K*mol

Explanation:

To solve this exercise we will use the knowledge and formulas of the reversible adiabatic expansion to calculate the value of Cp. In the attached image the answer given is calculated step by step.

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.