Answer this chemistry question image below

What is the chemical formula of the following compound

It is important to wear proper protective equipment in lab even when not actively performing experiments because accidents can affect any researcher, even one not working on an experiment. select the best answer from the choices provided

Which of these would be caused by a chemical change? a) the formation of lava. b) sedimantary rock layering over time. c) metamorphic rock forming from igneous. d) metamorphic rock eroding to form sedimentary rock.