Repetition, Year 9, Term 2, Second Sheet I) photon from a IR laser has less energy than a

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Repetition, Year 9, Term 2, Second Sheet

I) photon from a IR laser has less energy than a

A) microwave photon B) UV laser

C) radio wave photon D) none of the above

II) A photons from a red laser has more energy than a

A) IR photon B) UV photon

C) x-ray photon D) green photon

III) Fluor is the 9^th element in the periodic table. In the ground state, the electronic structure of Fluor is hence

A) 1s²2s²2p⁵ B) 1s²2s²3s²3p¹ C) 1s²2s²2p²3s²3p¹ D) 1s⁹

1) Calculate the photon energies associated with the transitions from the third energy level (n=3) to the ground level in both Hydrogen and Mercury using the energy diagram below:

2) Use the energy level diagram to state the ionization energy of Mercury in the ground state.

3) Calculate energy of the second energy level (n = 2) in Hydrogen.

4) Consider light with a frequency of

2.6× 10

Hint: Planck’s constant is 4.136×10⁻¹⁵eV⋅s ^.

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5) The energy of a photon from a green laser is 2.6 eV, which corresponds to 4.0×10^{−19 J.}

Consider a green laser with a power of 20 W. How many photons does this green laser emit each second, assuming that the efficiency of the laser is 30 %?

6) ^{2 38}₉₂U is an unstable isotope of Uranium that decays into and isotope of Thorium (Th) by alpha decay. Calculate A and Z for the daughter nucleus.

7) Take a look at the diagram in Figure 1 below:

Figure 1: The binding energy per nucleon.

a) Use the diagram above to estimate the total binding energy of 168

O

b) Use the diagram to estimate the energy released in the alpha decay of 36

Li

8) The mass of a proton is

167,26

kg

9) Calculate the binding energy of Fe-56 based on exercise 12.