When uranium-235 atoms undergo fission, is/are produced?

Iknow the answer is a but i don't know why

What are transitions between a liquid and gas called? identify which way they are transitioning

Which of the following describes a compound? (hint: carbon and oxygen bo a. a piece of pure carbon, containing only carbon atoms b. oxygen gas surrounding a solid piece of carbon c. a substance made of two oxygen atoms for each carbon atom carbon and oxygen atoms mixed without being bonded together