Atomic Structure

What is the equation for the first ionisation energy of a sodium atom?

• Na(g) -> Na⁺(g) + e^-

• Na⁺(g) -> Na²⁺(g) + e^-

• Na(s) -> Na⁺(g) + e

• Na⁺(g) + e^- -> Na(g)

Which electron configuration gives rise to the largest increase between the second and third ionisation energies?

• 1s² 2s² 2p²

• 1s² 2s² 2p⁶ 3s¹

• 1s² 2s² 2p⁶ 3s²

• 1s² 2s² 2p¹

Which element can have the following ionisation energies (in kJ/mol): 250, 500, 2500, 2800?

• K

• Mg

• O

• F

How many valence electrons does this atom have?

• 1

• 2

• 3

• 4

How many valence electrons does the element have?

IE1 = 943

IE2 = 1,950

IE3 = 3,852

IE4 = 5,492

IE5 = 23,085

IE6 = 26,791

IE7 = 30,024

• 2

• 3

• 4

• 5

The first seven ionisation energies of element M are 786, 1577, 3229, 4356, 16080, 19790 and 23780 kJ/mol.

Which group In the Periodic Table does element M belong to?

• 2

• 4

• 14

• 16

What is the electronic configuration of a Si atom?

• 1s² 2s² 2p²

• 1s² 2s² 2p⁴

• 1s² 2s² 2p⁶ 3s² 3p²

• 1s² 2s² 2p⁶ 3s² 3p⁴

Which ion has the same electronic configuration as O^2- ?

• Be²⁺

• Cl^-

• N^3-

• K⁺

The ⁶⁸Ge isotope is medically useful because it undergoes a natural radioactive process to give an isotope of a different element, ⁶⁸X, which can be used to detect tumours. This transformation of ⁶⁸Ge occurs when an electron enters the nucleus and changes a proton into a neutron.

Which statement about the composition of an atom of ⁶⁸X is correct?

• It has 4 electrons in its outer p orbitals.

• It has 13 electrons in its valence electron shell.

• It has 37 neutrons.

• Its proton number is 32.

Sodium azide, NaN₃ is an explosive used to inflate airbags in cars when they crash. It consists of positive sodium ions and negative azide ions.

What are the numbers of electrons in the sodium ion and the azide ion?

• A

• B

• C

• D