Which of the following rocks from the chart would probably be densest? (Granite, andesite, scoria, pumice, diorite)

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.

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?

If a solution contains 3 moles/liter of sodium chloride (nacl, made of sodium ions and chloride ions), what is the osmolarity of this solution