When the value of entropy is greater,then the ability of work

Given that $\Delta H = 0$ for the mixing of two gases,explain whether the diffusion of these gases into each other in a closed container is a spontaneous process or not?

For which of the following processes is the entropy change $(\Delta S)$ negative?
$I)$ Sublimation of dry ice
$II)$ Freezing of water
$III)$ Crystallisation of the dissolved substance
$IV)$ Burning of rocket fuel

Which of the following reactions has a positive entropy change?

In which of the following processes does entropy increase?

According to the second law of thermodynamics,which of the following is true for a spontaneous process?