Suppose you want to convert a gas into a liquid. Which two methods can you apply ?

Suppose you want to grow a garden like the one shown in the picture, around your home or school. What would you do to achieve that? By which methods will you cultivate the seedlings

The process by which gas is converted into liquid:

How can you convert ethanol to methanol ?

Emulsion can be converted into two separate liquids by:

How can you convert ethanol to ethene ?