Question

Briefly define (one sentence each) these phrases:

1. adiabatic process

2.isothermal process

Calculate the heat required to raise the temperature of 1.450 mol of lead from 20 °C to 357 °C at constant pressure given that for lead,

C _p.m  /J K^–1 mol^–1 = a + bT + c/T²

where a = 22.13, b= 11.72 ´ 10^–3 K^–1, c = 0.96 x 10⁵ K²

and T is the absolute (kelvin) temperature.

Answer 1

1) An adiabatic process is a thermodynamic process in which there is no heat transfer into or out of a system and is generally obtained by surrounding the entire system with a strongly insulating material or by carrying out the process so quickly that there is no time for a significant heat transfer to take place.

2) An isothermal process is a process in which the temperature of a system remains constant. The transfer of heat into or out of the system happens so slowly that thermal equilibrium is maintained.