if 22 grams of benzoic acid, HC6H5CO2, is dissolved in 1.0L of water, the [H+] is found to br 8.0 x 10-4M. Calculate the Ka for benzoic acid

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 of the following is a physical change? a. burning a piece of wood b. sawing a piece of wood in half c. rust forming on an iron fence d. a copper roof changing color from orange to green

The molar mass of iron(fe) is 55.8 g/mol. what is the mass in grams of 2.25 moles of iron?