Describe how an element's position in the Periodic Table is connected to its electronic configuration.
Aluminium is in Group III of the Periodic Table. Deduce the electronic configuration of the aluminium ion.
Aluminium reacts with oxygen to produce aluminium oxide, $\text{Al}_2\text{O}_3$. Write the equation for this reaction.
Aluminium oxide reacts with both acids and alkalis. State the type of oxide that reacts with both acids and alkalis.
Draw a dot-and-cross diagram for an oxygen molecule. Show only the outer-shell electrons.
Describe and explain how the diffusion rates of oxygen and nitrogen differ.
Oxygen reacts with hydrogen to make water. Sulfur reacts with hydrogen to make hydrogen sulfide. Some properties of hydrogen sulfide are listed: it is a gas at room temperature; it reacts with aqueous sodium hydroxide; it is a reducing agent; it burns in air. Describe four differences between the properties of water and those of hydrogen sulfide.