What is the standard enthalpy of formation for a compound? For a pure element in its standard state?

Solution: Here, we are going to calculate and compare the energy of the photons emitted by the given two radio stations. Step1: According to Planck’s quantum theory of radiation, the amount of energy associated with a quantum(in case of light, the quantum of energy is often called photon) of radiation is proportional to the frequency of light, E = h ---(1), where h is a universal constant called Planck’s constant. is the frequency and E is the energy of a photon. Step2: Given, frequency of the photon = 1010 KHz = 1010 x 10 s 3 -1 [1 KHz = 1000 Hz = 1000 s ] -1 = 1.010 x 10 s 6 -1 -34 Planck's constant, h = 6.626 x 10 J.s Substituting the values in equation (1), we get, E = (6.626 x 10 J.s) x (1.010 x 10 s ) 6 -1 -28 = 6.69 x 10 J...