EXAM QUESTIONS AND ANSWERS 100

A LEVEL CHEMISTRY Exam Atomic Structure

EXAM QUESTIONS AND ANSWERS 100%

SOLVED (Newest 2025) What is the difference between the values of the 1st and 2nd ionisation energies of iron. Explain your answer. - Correct Answers ✅- The second ionisation is higher.

• The second electron is removed from a positive ion.

Therefore, there is greater attraction between the 2nd electron and the nucleus.Explain why Aluminium has a lower 1st IE than Magnesium - Correct Answers ✅- An electron is removed from the 3p subshell of Al

• An electron is removed from the 3s subshell of Mg
• The 3s subshell is higher in energy than 3s

Explain why Oxygen has a lower 1st IE in Nitrogen - Correct Answers ✅- The first electron removed from Nitrogen is in a 2p orbital and is unpaired

• The first electron removed from oxygen is in a 2p orbital and

is paired

• Paired electrons repel, so less energy is required to remove

the electron from oxygen.The trend in 2nd ionisation energy across period 3 follows the same pattern. Suggest which elements deviate from the general increase in ionisation energy when the 2nd ionisation energy is measured - Correct Answers ✅Si and Cl 1 / 2

A LEVEL CHEMISTRY Exam Atomic Structure

EXAM QUESTIONS AND ANSWERS 100%

SOLVED (Newest 2025) Element X is a period 2 element, interpret the data to determine its identity. (Ionisation energies)

1= 1090

2 = 2350

3 = 4610

4 = 6220

5 = 37800

• = 47000 - Correct Answers ✅- The largest increase in

ionisation energy is between the 4th and 5th ionisation energies

• The 5th electron must be taken from a shell closer to the

nucleus.

• Therefore, the element has 4 outer electrons.
• X = carbon

Sodium has a lower 1st ionisation than both Ne and Mg, explain for each element why this is the case. - Correct Answers ✅- Mg has more protons AND the same shielding as Na

• Therefore the outer electron in Mg is more strongly

attracted to the nucleus and requires more energy to remove it.

• Ne has its outer electron on a shell closer to the nucleus, so

there is less shielding.

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