If you talk about the process of fission in the nuclear field then the most used is U-235 because is the easiest to use. Have in mind that the majority of uses of uranium is U-238 but the easiest to be used is U-235
Depends on whether the person is talking to themselves, or someone else.
If they are talking to themselves, it is indeed intrinsic motivation, as they are convincing themselves they are also happy and motivated to join the science club as it makes their parents happy.
If they are talking to someone else, it would not be intrinsic motivation. This is because they are merely telling someone that they're doing something to make their parents happy.
As it is a statement, on the whole I would say, no. It is not intrinsic motivation.
The kitchen, because the chloroplast is the site of glucose production. In houses, kitchens are where you make food.
