Atomic structure: Practice Questions

Which statement correctly describes atomic orbitals?

Which statement correctly explains the general trend in first ionisation energy across Period 3?

The first ionisation energy of magnesium is \( 738 \text{ kJ mol}^{-1} \), while the first ionisation energy of aluminium is \( 578 \text{ kJ mol}^{-1} \).
Which statement provides the correct explanation for why aluminium has a lower first ionisation energy than magnesium?

How many protons, neutrons and electrons are there in an ion of \(^{39}\text{K}^+\)?

H o w m a n y o r b i t a l s c o n t a i n a t l e a s t o n e e l e c t r o n i n a n a t o m o f m a g n e s i u m , \( e x t{M g} \), i n i t s g r o u n d s t a t e ?

A beam of protons and a beam of neutrons are passed through an electric field. Describe the difference in the behavior of these two beams as they pass through the field.

Describe the trend in atomic radius across Period 3 from sodium to chlorine and explain this trend in terms of nuclear charge and shielding.

An element has successive ionisation energies (in kJ mol\(^{-1}\)) of 738, 1450, 7733, 10540, 13360. Deduce the group number of this element in the Periodic Table and explain your reasoning.

The chemical properties of an element are determined by its electronic configuration.

(a) Define the term isotope in terms of sub-atomic particles.
(b) Explain why \( ^{35}\text{Cl} \) and \( ^{37}\text{Cl} \) have identical chemical properties.
(c) State one physical property that differs between these two isotopes and explain why it differs.

Successive ionisation energies provide evidence for the electronic structure of atoms.

(a) Define the term first ionisation energy.
(b) Write an equation, including state symbols, to represent the second ionisation energy of magnesium.
(c) Explain why the first ionisation energy of aluminum (atomic number = 13) is lower than that of magnesium (atomic number = 12).