Ionisation energies

Question 1

explain why it takes more energy to remove each successive electron.

Answer 1

The electrons are being move from an increasingly positive ion so more energy is needed to remove an electron

Question 2

state and explain the trend in first ionisation energies across P3.

Answer 2

• Ionisations energies increase along P3

• no. protons increase so the atomic radius decreases
• no. electrons in the outer shell increases but there is no extra shielding
• Both of these factors strengthen the attraction between the nucleus and the outer electrons.
• ionisation energies decreased slightly between Mg and Al.
• this is because Al’s outer electrons are in the p orbital so it’s slightly further away from the nucleus.
• ionisation energies decrease between P and S
• this is because S outer electrons are being removed from an orbital contains 2 electrons. opposite spins causes repulsion therefore making the electron easier to remove