Why does a solid have a definite shape? the particles of a solid vibrate in fixed positions. the particles of a solid have no forces of attraction between them. the particles of a solid cannot change shape. the particles of a solid cannot move at all.

Select for each of the following statements whether it is correct or incorrect. (a) in an isothermal expansion of an ideal gas. (b) the temperature remains constant. (b) the pressure remains constant. (c) there is work done by the gas. (d) there is heat added to the gas. (e) the change in internal energy equals zero.