How is there gravity on earth but not in space?
Beaker is pyrex glass which won't shatter when heating and cooling. Also, glass does not react with very many compounds (beware of HF, hydrofluoric acid tho). The stirring increase the surface area exposed to the solvent if the material dissolving is a solid, otherwise it just speeds up the mix. Precautions are a minimum of Safety glasses, rubber gloves, and a smock. Preferably use a face mask as well, and a hood that removes vapors.
yes you can. companies can ask you to cut your hair, take out piercings, etc. to uphold a professional demeanor and if you physically cannot do that (because tattoos are permanent), then they are within their rights to fire you (or not hire you in the first place). Example: it is bad business for a restaurant employee to have long, unkept hair, or too much facial hair when working closely with food. The restaurant can ask you to cut it or tie it back, and they can fire you if you refuse. If you work for a financial management company and people are trusting you with their retirement money, you need to look collected, intelligent and put together. Company employees need to be clean, well-dressed, and professional. If they deem that having tattoos is not in concordance with their policies or their business model, you can be fired.
