This question is about oxygen and substances containing oxygen - AQA - GCSE Chemistry - Question 3 - 2017 - Paper 1

The type of bonding in an oxygen molecule is covalent bonding.

Oxygen has a low boiling point due to weak intermolecular forces between the molecules. These weak van der Waals forces require little energy to overcome, which results in a relatively low boiling point for oxygen.

The balanced equation for the reaction of magnesium and oxygen is:

$2 \text{Mg} + \text{O}_2 \rightarrow 2 \text{MgO}$

When magnesium reacts with oxygen, magnesium loses two electrons to achieve a stable electronic configuration similar to that of noble gases. These lost electrons are gained by oxygen atoms, which then become negatively charged oxide ions (O²⁻). This electron transfer leads to the formation of ionic bonds between the magnesium ions (Mg²⁺) and oxide ions.

Nanoparticles are particles that range from 1 to 100 nanometers in size. They typically contain a few hundred atoms and have a high surface area to volume ratio, which gives them unique physical and chemical properties.

Silicon dioxide (SiO₂) has a high melting point because of its strong covalent bonds within a giant molecular structure. Breaking these bonds requires a significant amount of energy, making SiO₂ suitable for furnace linings, as it can withstand high temperatures without melting.