Asample of methane gas of mass 35 g at 250 k and 12.5 atm expands isothermally until its
pressure is 1.5 atm. determine the change in entropy of the gas.

yes definetly because you are using energy

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.