Summary
Metals are used in various applications due to their unique physical and chemical properties. They are often combined with other elements to form alloys, which have enhanced properties compared to pure metals.
- Alloy — a mixture of a metal with other elements. Example: Brass is an alloy of copper and zinc.
- Malleable — ability of metals to be shaped or bent without breaking. Example: Gold is highly malleable and can be hammered into thin sheets.
- Ductile — ability of metals to be drawn into wires. Example: Copper is ductile and used in electrical wiring.
- Galvanizing — process of applying a protective zinc coating to steel or iron to prevent rusting. Example: Zinc is used to galvanize steel.
- Stainless Steel — an alloy of iron, chromium, and sometimes nickel, known for its resistance to corrosion. Example: Used in cutlery and surgical instruments.
Exam Tips
Key Definitions to Remember
- Alloy: A mixture of a metal with other elements.
- Malleable: Ability to be shaped or bent without breaking.
- Ductile: Ability to be drawn into wires.
Common Confusions
- Confusing alloys with compounds; alloys are mixtures, not chemically bonded.
- Mistaking corrosion for rust; rust specifically refers to iron or steel oxidation.
Typical Exam Questions
- What is an alloy? An alloy is a mixture of a metal with other elements.
- Why is stainless steel used in cutlery? Because it is resistant to corrosion.
- How does galvanizing prevent rust? By applying a protective zinc coating to steel or iron.
What Examiners Usually Test
- Understanding of why alloys are used instead of pure metals.
- Knowledge of the properties and uses of specific metals and alloys.
- Ability to explain the process and purpose of galvanizing.