an 8.925 g sample of a compound containing only, carbon, hydrogen , and oxygen gives 9.258 g of carbon dioxide and 5.351 g 0f water after complete combustion of the sample. what is the mass percentage of the sample

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

Find the number of grams of hcl needed to react completely with .50 moles of magnesium.

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?