Plants need from the air for photosynthesis. A. carbon dioxide B. soil
C. oxygen D. carbon monoxid

Which statement best describes the he properties of iconic compounds ?

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?

Which states of matter have particles that move independently of one another with very little attraction?