Question

Answer the following questions:

a). The heat of fusion of ice is 6.00 kJ/mol. Find the number of photons of wavelength = 6.27 10-6 m that must be absorbed to melt 3.00 g of ice

b). The energy required to ionize potassium is 419 kJ/mol. What minimum frequency of light is required to ionize potassium?

c). An X-ray photon of wavelength 0.920 nm strikes a surface. The emitted electron has a kinetic energy of 936 eV. What is the binding energy of the electron in kJ/mol? [KE = .5 mv2; 1 electron volt (eV) = 1.602 10-19 J]

Answer 1

a)

number of mol of Ice = mass/molar mass

                     = 3/18

                     = 1/6 mol

heat required = heat of fusion * number of mol

              = 6.00 KJ/mol * (1/6)mol

              = 6.00 KJ

              = 6000 J

energy of 1 photon = h*c/wavelength

                   = (6.626*10^-34)*(3*10^8)/(6.27*10^-6)

                   =3.17*10^-20 J

number of photon = 6000 J / (3.17*10^-20)

                  = 1.89*10^23

Answer: 1.89*10^23

Other questions are not related to this one.

I am allowed to answer only 1 question at a time