Some things that are difficult or impossible on Earth are practical in space. For example, it may be possible to create valuable chemical compounds in microgravity that could not be made on Earth. On the other hand, some routine tasks on Earth can be challenging in microgravity. There is research that focuses on ways to make life healthier and more comfortable for astronauts. SEM experiments are subject to microgravity for hours or days, a condition which simply does not occur on Earth.
Chemical reaction requires some kind of mixing or diffusion process.
On earth this process is strongly shaped by gravity. Even the shape of a flame changes depending on the presence or absence of gravity. Everything from the rate of reactions to their yield could be affected in interesting and possibly useful ways. Although plants do grow in space and astronauts do regain their sense of balance, many interesting questions can be formed around the adaptations of biology to space travel. If space is our future, then answers to these questions will help us get there sooner.