Chemical Changes: Metals

Chemical Changes: Metals

Chemical Reactions of Metals

• Metals can undergo a variety of chemical changes, and it’s crucial to understand these to predict and explain observations in chemistry.
• Oxidation reactions involve the addition of oxygen to a substance. For instance, when metals react with oxygen, metal oxides are produced.

Reduction and Oxidation

• Reduction is the loss of oxygen, while oxidation is the gain of oxygen. Remember the helpful acronym ‘OIL RIG’.
• Oxidation is loss, Reduction is gain, referencing the loss or gain of electrons respectively.

The Reactivity Series

• Metals are arranged according to their reactivity in a list known as the reactivity series. Potassium is the most reactive and gold is the least reactive.
• The reactivity of a metal can be determined by its reactions with water and acids, and displacement reactions with other metals.

Displacement Reactions

• In a displacement reaction, a more reactive metal will displace a less reactive metal from its compound.
• When iron reacts with copper sulfate, for instance, it displaces the copper because iron is more reactive.

Extraction of Metals

• Metals that are less reactive than carbon can be extracted from their ores by reduction with carbon.
• The method of extraction for a metal depends on its position in the reactivity series.

Corrosion

• Corrosion is a form of oxidation. Rust is a form of iron oxide and forms when iron corrodes.
• Prevention techniques like galvanising, painting, and using sacrificial metals can help inhibit corrosion.