Ibuprofen, a common pain remedy, has an empirical formula of c7h9o and a molar mass of approximately 218.078 grams per mole. what is the molecular formula of ibuprofen?

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

How do dying stars contribute to the formation of planets

What four properties do all waves have in common