A 0.500-g sample of chromium metal reacted with sulfur powder to give 0.963 g of product. Calculate the empirical formula of the chromium sulfide.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

answer: mole of the gas

answer: mole of the gasexplanation:

alchemy hadn't scientific methods of study, appeal to mysticism and fantasy, the knowledge of chemistry and physics were modest at that time.

alchemy was - but as new rules were discovered it either changed into chemistry or it became "unscientific".