1+2. These questions are about this element lithium. The symbol is shown here :

1. What are the values of N, Z and A for this stable isotope of lithium?

• A. A = 4, N = 7, Z = 3.
• B. A = 3, N = 7, Z = 4.
• C. A = 7, N = 4, Z = 3.
• D. A = 7, N = 3, Z = 4.

2. When small samples of lithium are put in a bunsen burner flame a characteristic crimson red colour is seen. This colour from the emission spectrum of lithium is evidence for...

• A. discrete nuclear energy levels
• B. discrete atomic energy levels
• C. continous nuclear energy levels
• D. continous atomic energy levels

3-5. The diagram below shows the Rutherford-Geiger-Marsden experiment. It involved firing particles at thin gold leaf foil.

• A. alpha
• B. beta
• C. protons
• D. neutrons

4. The experiment proved the existence of ...

• A. a small dense nucleus
• B. neutrons in the nucleus
• C. atomic energy levels
• D. electron shells

5. What result led Rutherford to conclude that most of the atom was 'empty space'?

• A. Most of the particles bounced back at the source, with few being deflected.
• B. Most of the particles were deflected through small angles, with few continuing straight through the foil.
• C. Most of the particles were absorbed, with few continuing straight through the foil.
• D. Most of the particles went straight through the gold foil, with few being deflected.

6. A photon of light has an energy of E and a wavelength of λ. Which of these formulas is correct?

• A. $λ = {{h} \over {cE}}$
• B. $λ = {{hc} \over {E}}$
• C. $λ = {{E} \over {hc}}$
• D. $λ = {{c} \over {hE}}$

Q7-10. This diagram shows electron energy levels in a hydrogen atom. Only the first 4 energy levels are shown.

Emission or absorption of a photon is associated with an electron jump between energy levels.

For the following questions, only jumps between the 4 energy levels shown are considered.

(Not to scale -approximate energy level values).

7. Which energy level change will emit a photon with the highest frequency?

• A. From n = 4 to n = 1.
• B. From n = 1 to n = 4.
• C. From n = 3 to n = 4.
• D. From n = 4 to n = 3.

8. At n = ∞, which of these statements is true?

• A. The energy level of the electron is infinite, the electron is still orbiting the nucleus.
• B. The energy level of the electron is zero, the electron is still orbiting the nucleus.
• C. The energy level of the electron is zero, the electron is ionised.
• D. The energy level of the electron is infinite, the electron is ionised.

9. Cold hydrogen gas in space is subjected to a wide spectrum of radiation from the Sun. Which of these statements best describes the absorption and emission of radiation by the hydrogen gas?

• A. A wide range of a frequencies is absorbed, and a narrow range of specific frequencies re-radiated in all directions.
• B. A wide range of a frequencies is absorbed, and a wide range re-radiated in all directions.
• C. A narrow range of specific frequencies is absorbed, and a narrow range of specific frequencies re-radiated in all directions.
• D. A narrow range of specific frequencies is absorbed, and a wide range re-radiated in all directions.

10. Photons of visible light have energy of between 1.8 and 3.1 eVs. Which of the following transitions is likely to emit an infrared light photon?

• A. From n = 3 to n = 2.
• B. From n = 2 to n = 4.
• C. From n = 4 to n = 2.
• D. From n = 4 to n = 3.